TEDS Data Dictionary

Variables in the 9 Year Dataset

The table on this page lists all 9 Year variables. This includes all item variables from the 9 Year booklets, as well as derived variables that are based on 9 Year items.

The table does not include background variables that originate from other sources (either from admin data or from other study datasets). Such variables include IDs, twin sex and zygosity variables, the random variable and general exclusion variables. See the background variables page for details.

Variables are listed in alphabetical order in the table below. The columns of the table are:

  • Dataset variable name
  • Dataset variable label (in SPSS)
  • Source of data:
    • child - from the twin booklet
    • parent - from the parent booklet
    • teacher - from the teacher booklet
    • admin - administrative data, logged in the TEDS admin database
  • Item or derived variable? - see item coding for the parent, child and teacher booklets (pdfs) for item variables; see also the description of derived variables for more information.
  • Data type:
    • integer - numeric whole numbers
    • decimal - numeric with fractional values
  • Variable type:
    • nominal - categorical, with arbitrary numeric values
    • ordinal - categorical, with ordered numeric values
    • quantitative - numerical measurements of some concrete quantity such as age
    • scale value - numerical measurement derived (usually) as a sum or mean of other variables
  • Coding or range of values - this shows the value coding used for nominal/ordinal variables, or an approximate range of values for quantitative and scale variables.
dataset variable namedataset variable labelsource of dataitem or derived variable?data typevariable levelcoding or approximate range of values
iadultsHousehold category: adults present (parent at 9), see value labelsparentderivedintegernominal 1=biological mother and father, 2=mother or father with guardian/other, 3=single parent, 9=other or unknown
icbpimp1/2Being a parent: parent gets impatient (child at 9), see value labelschilditemintegerordinal 0=never, 1=sometimes, 2=often
icbphap1/2Being a parent: happy about parent relationship (child at 9), see value labelschilditemintegerordinal 0=never, 1=sometimes, 2=often
icbphapr1/2Reversed version of icbphap, see value labels childitemintegerordinal0=often, 1=sometimes, 2=never
icbpamu1/2Being a parent: parent finds me funny (child at 9), see value labelschilditemintegerordinal 0=never, 1=sometimes, 2=often
icbpamur1/2Reversed version of icbpamu, see value labels childitemintegerordinal0=often, 1=sometimes, 2=never
icbpalo1/2Being a parent: parent wishes I would leave alone (child at 9), see value labelschilditemintegerordinal 0=never, 1=sometimes, 2=often
icbpang1/2Being a parent: I make parent angry (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
icbpclo1/2Being a parent: I feel close to parent (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
icbpclor1/2Reversed version of icbpclo, see value labels childitemintegerordinal0=very true, 1=quite true, 2=not true
icbpfru1/2Being a parent: I make parent frustrated (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
iccacce1/2CEQ Acceptance (child) mean scale at 9, 0-2 childderiveddecimalscale value0 to 2
iccadve1/2CEQ Adventure (child) mean scale at 9, 0-2 childderiveddecimalscale value0 to 2
iccas011/2Behaviour: important to fit in (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas01r1/2Reversed version of iccas01, see value labelschilditemintegerordinal0=very true, 1=quite true, 2=not true
iccas021/2Behaviour: odd way of talking (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas031/2Behaviour: have unusual interest (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas041/2Behaviour: focussed on myself (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas051/2Behaviour: conversation difficult (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas061/2Behaviour: same interests as friends (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas06r1/2Reversed version of iccas06, see value labelschilditemintegerordinal0=very true, 1=quite true, 2=not true
iccas071/2Behaviour: nervous habits (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas081/2Behaviour: easy to remember facts (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas091/2Behaviour: say rude things by mistake (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas101/2Behaviour: I like to talk about (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas111/2Behaviour: others cannot follow me (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas121/2Behaviour: like to stick to routines (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas131/2Behaviour: do things over and over (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas141/2Behaviour: like stories (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas14r1/2Reversed version of iccas14, see value labelschilditemintegerordinal0=very true, 1=quite true, 2=not true
iccas151/2Behaviour: show other people (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas15r1/2Reversed version of iccas15, see value labelschilditemintegerordinal0=very true, 1=quite true, 2=not true
iccas161/2Behaviour: difficult to look in eye (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas171/2Behaviour: get on with other children (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas17r1/2Reversed version of iccas17, see value labelschilditemintegerordinal0=very true, 1=quite true, 2=not true
iccas181/2Behaviour: other people important (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas18r1/2Reversed version of iccas18, see value labelschilditemintegerordinal0=very true, 1=quite true, 2=not true
iccas191/2Behaviour: care what friends think (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccas19r1/2Reversed version of iccas19, see value labelschilditemintegerordinal0=very true, 1=quite true, 2=not true
iccas201/2Behaviour: get wrong end of stick (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
iccascomt1/2CAST Communication scale at 9 (child self-report), 0-12childderiveddecimalscale value 0 to 12
iccasnont1/2CAST Non-Social scale at 9 (child self-report), 0-12 childderiveddecimalscale value0 to 12
iccassoct1/2CAST Social scale at 9 (child self-report), 0-16 childderiveddecimalscale value0 to 16
iccastt1/2CAST overall total at 9 (child self-report), 0-40 childderiveddecimalscale value0 to 40
icchaos11/2Chaos: regular bedtime routine (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
icchaos1r1/2Reversed version of icchaos1, see value labels childitemintegerordinal0=very true, 1=quite true, 2=not true
ichaos21/2Chaos: cannot hear yourself think (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
ichaos31/2Chaos: a real zoo (child at 9), see value labels childitemintegerordinal0=not true, 1=quite true, 2=very true
ichaos41/2Chaos: able to stay on top of things (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
ichaos4r1/2Reversed version of icchaos4, see value labels childitemintegerordinal0=very true, 1=quite true, 2=not true
ichaos51/2Chaos: usually a TV turned on (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
ichaos61/2Chaos: calm atmosphere (child at 9), see value labels childitemintegerordinal0=not true, 1=quite true, 2=very true
ichaos6r1/2Reversed version of icchaos6, see value labels childitemintegerordinal0=very true, 1=quite true, 2=not true
icchato1/2Child Chaos scale at 9, 0-12child deriveddecimalscale value0 to 12
iccla011/2Classroom: like to be (child at 9), see value labels childitemintegerordinal0=not true, 1=somewhat true, 2=certainly true
iccla021/2Classroom: accepted by other children (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla031/2Classroom: work will help in future (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla041/2Classroom: feel upset (child at 9), see value labels childitemintegerordinal0=not true, 1=somewhat true, 2=certainly true
iccla051/2Classroom: work is interesting (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla061/2Classroom: friends care about work (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla071/2Classroom: teacher takes an interest (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla081/2Classroom: feel unhappy (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla091/2Classroom: get on with other children (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla101/2Classroom: have a lot of fun (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla111/2Classroom: get excited about work (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla121/2Classroom: will help in 2ndary school (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla131/2Classroom: feel lonely (child at 9), see value labels childitemintegerordinal0=not true, 1=somewhat true, 2=certainly true
iccla141/2Classroom: teacher treats me fairly (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla151/2Classroom: like to do extra work (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla161/2Classroom: friends try their best (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla171/2Classroom: teacher helps do my best (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla181/2Classroom: feel worried (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla191/2Classroom: learn things I care about (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla201/2Classroom: friends enjoy learning (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla211/2Classroom: teacher listens (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla221/2Classroom: feel happy (child at 9), see value labels childitemintegerordinal0=not true, 1=somewhat true, 2=certainly true
iccla231/2Classroom: people think a lot of me (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla241/2Classroom: learning will be useful (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla251/2Classroom: proud to be a pupil (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla261/2Classroom: friends often in trouble (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla271/2Classroom: popular with other children (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccla281/2Classroom: learning is fun (child at 9), see value labelschilditemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iccnega1/2CEQ Negative Affect (child) mean scale at 9, 0-2 childderiveddecimalscale value0 to 2
iccoppo1/2CEQ Opportunity (child) mean scale at 9, 0-2 childderiveddecimalscale value0 to 2
iccpeer1/2CEQ Friends/Peer Context (child) mean scale at 9, 0-2 childderiveddecimalscale value0 to 2
iccsati1/2CEQ Classroom Satisfaction (child) mean scale at 9, 0-2childderiveddecimalscale value 0 to 2
iccteac1/2CEQ Teachers (child) mean scale at 9, 0-2 childderiveddecimalscale value0 to 2
icdata1/2Child booklet data present at 9, 1Y 0Nchild itemintegernominal0=no, 1=yes
icdiask1/2Discipline: parents ask someone else (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
icdiexp1/2Discipline: parents explain (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
icdiexr1/2Reversed version of icdiexp1, see value labels childitemintegerordinal0=very true, 1=quite true, 2=not true
icdifir1/2Discipline: parents are firm (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
icdifrr1/2Reversed version of icdifir1, see value labels childitemintegerordinal0=very true, 1=quite true, 2=not true
icdijok1/2Discipline: parents make a joke (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
icdisavot1/2Parental discipline avoidance scale, child-self-rated, 0-4 childderiveddecimalscale value0 to 4
icdisho1/2Discipline: told off or shouted at (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
icdisma1/2Discipline: smacked (child at 9), see value labels childitemintegerordinal0=not true, 1=quite true, 2=very true
icdisnegt1/2Parental discipline negative/harsh scale, child-self-rated, 0-4 childderiveddecimalscale value0 to 4
icdispost1/2Parental discipline positive scale, child-self-rated, 0-4 childderiveddecimalscale value0 to 4
icg1/2G composite (9 year child), standardisedchild deriveddecimalscale valueapprox. -3 to +3 (standardized)
icgen011/2General Knowledge Quiz item 1 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen021/2General Knowledge Quiz item 2 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen031/2General Knowledge Quiz item 3 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen041/2General Knowledge Quiz item 4 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen051/2General Knowledge Quiz item 5 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen061/2General Knowledge Quiz item 6 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen071/2General Knowledge Quiz item 7 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen081/2General Knowledge Quiz item 8 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen091/2General Knowledge Quiz item 9 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen101/2General Knowledge Quiz item 10 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen111/2General Knowledge Quiz item 11 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen121/2General Knowledge Quiz item 12 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen131/2General Knowledge Quiz item 13 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen141/2General Knowledge Quiz item 14 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen151/2General Knowledge Quiz item 15 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen161/2General Knowledge Quiz item 16 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen171/2General Knowledge Quiz item 17 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgen181/2General Knowledge Quiz item 18 score (child at 9), 1right 0wrongchildderivedintegerordinal 0=incorrect, 1=correct
icgenh1/2General Knowledge Quiz, parent helped twin read questions (child at 9), 1Y 0Nchilditeminteger nominal0=no, 1=yes
icgent1/2General Knowledge test total score (child at 9), 0-18 childderivedintegerscale value0 to 18
icgoo011/2Good at reading (child at 9), see value labels childitemintegerordinal1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
icgoo021/2Good at writing (child at 9), see value labels childitemintegerordinal1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
icgoo031/2Good at spelling (child at 9), see value labels childitemintegerordinal1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
icgoo041/2Good at solving number problems (child at 9), see value labelschilditemintegerordinal 1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
icgoo051/2Good at mental arithmetic (child at 9), see value labelschilditemintegerordinal 1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
icgoo061/2Good at multiplying and dividing (child at 9), see value labelschilditemintegerordinal 1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
icgoo071/2Good at learning about nature (child at 9), see value labelschilditemintegerordinal 1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
icgoo081/2Good at testing things out (child at 9), see value labelschilditemintegerordinal 1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
icgoo091/2Good at finding out how things work (child at 9), see value labelschilditemintegerordinal 1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
icgoo101/2Good at team games (child at 9), see value labels childitemintegerordinal1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
icgoo111/2Good at races and competitions (child at 9), see value labelschilditemintegerordinal 1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
icgoo121/2Good at PE classes (child at 9), see value labels childitemintegerordinal1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
ichom011/2Home: parents set aside HW time (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
ichom021/2Home: TV usually on during HW (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
ichom031/2Home: often ask for help with HW (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
ichom041/2Home: helped with HW should be done alone (child at 9), see value labelschilditeminteger ordinal0=not true, 1=quite true, 2=very true
ichom051/2Home: nights per week HW set (child at 9), see value labelschilditemintegerordinal 0=0, 1=1, 2=2, 3=3, 4=4, 5=5 or more
ichom061/2Home: hours per night doing HW (child at 9), see value labelschilditemintegerordinal 0=half or less, 1=1, 2=2, 3=3, 4=over 3
ichom071/2Home: parents think education important (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
ichom081/2Home: parents think doing best important (child at 9), see value labelschilditeminteger ordinal0=not true, 1=quite true, 2=very true
ichom091/2Home: discuss school with parents (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
ichom101/2Home: parents are interested in marks (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
ichom171/2Home: often read for fun (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
ichom181/2Home: parent often reads to me (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
ichom191/2Home: taken to museum in past year (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
ichom201/2Home: I use computer at home (child at 9), see value labelschilditemintegerordinal 0=not true, 1=quite true, 2=very true
ichom211/2Home: how many childrens books (child at 9), see value labelschilditemintegerordinal 0=0, 1=1-5, 2=6-10, 3=11-20, 4=21-30, 5=31 or more
ichom221/2Home: hours of TV watched school day (child at 9), see value labelschilditemintegerordinal 0=0, 1=1, 2=2, 3=3, 4=4, 5=5 or more
ichom231/2Home: hours of TV watched weekend day (child at 9), see value labelschilditemintegerordinal 0=0, 1=1, 2=2, 3=3, 4=4, 5=5 or more
ichom321/2Home: evening meals per week with parent (child at 9), 0-7childitemintegerquantitative 0 to 7
ichom331/2Home: hours of sleep per school night (child at 9), see value labelschilditemintegerordinal 0=6 or less, 1=7, 2=8, 3=9, 4=10, 5=11 or more
icliaca1/2Academic Liking scale, Child-self-rated at 9 (1-5) childderiveddecimalscale value1 to 5
iclieng1/2English Liking scale, Child-self-rated at 9 (1-5) childderiveddecimalscale value1 to 5
iclik011/2Like reading (child at 9), see value labels childitemintegerordinal1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
iclik021/2Like writing (child at 9), see value labels childitemintegerordinal1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
iclik031/2Like spelling (child at 9), see value labels childitemintegerordinal1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
iclik041/2Like solving number problems (child at 9), see value labelschilditemintegerordinal 1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
iclik051/2Like mental arithmetic (child at 9), see value labels childitemintegerordinal1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
iclik061/2Like multiplying and dividing (child at 9), see value labelschilditemintegerordinal 1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
iclik071/2Like learning about nature (child at 9), see value labelschilditemintegerordinal 1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
iclik081/2Like testing things out (child at 9), see value labelschilditemintegerordinal 1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
iclik091/2Like finding out how things work (child at 9), see value labelschilditemintegerordinal 1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
iclik101/2Like team games (child at 9), see value labels childitemintegerordinal1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
iclik111/2Like races and competitions (child at 9), see value labelschilditemintegerordinal 1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
iclik121/2Like PE classes (child at 9), see value labels childitemintegerordinal1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
iclimat1/2Maths Liking scale, Child-self-rated at 9 (1-5) childderiveddecimalscale value1 to 5
icliphy1/2Physical Education Liking scale, Child-self-rated at 9 (1-5)childderiveddecimalscale value 1 to 5
iclisci1/2Science Liking scale, Child-self-rated at 9 (1-5) childderiveddecimalscale value1 to 5
icmoaca1/2Academic Overall Motivational scale, Child-self-rated at 9 (1-5)childderiveddecimalscale value 1 to 5
icnv1/2Non-Verbal composite (9 year child), standardised childderiveddecimalscale valueapprox. -3 to +3 (standardized)
icodd11/2Behaviour: argue with adults (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icodd21/2Behaviour: refuse to obey adults (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icodd31/2Behaviour: annoy people on purpose (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icodd41/2Behaviour: easily get annoyed (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icodd51/2Behaviour: often angry (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icoddt1/2ODD total scale (child self-rated at 9), 0-10childderiveddecimalscale0 to 10
icohortCohort for 9yr study, see value labelsadmin itemintegernominal 1=school cohort 1: twins born Jan-94 to Aug-94, 2=school cohort 2: twins born Sep-94 to Aug-95
icpaaca1/2Academic Perceived Ability scale, Child-self-rated at 9 (1-5)childderiveddecimalscale value 1 to 5
icpaeng1/2English Perceived Ability scale, Child-self-rated at 9 (1-5)childderiveddecimalscale value 1 to 5
icpageAge of twins (years) when parent and child booklets completed at 9parent, adminderiveddecimal quantitativeapprox. 8.4 to 10 (years)
icpamat1/2Maths Perceived Ability scale, Child-self-rated at 9 (1-5)childderiveddecimalscale value 1 to 5
icpaphy1/2Physical Education Perceived Ability scale, Child-self-rated at 9 (1-5)childderiveddecimal scale value1 to 5
icparnegt1/2Negative parental feelings scale, child-self-rated at 9, 0-8 childderiveddecimalscale value0 to 8
icparpost1/2Positive parental feelings scale, child-self-rated at 9, 0-6 childderiveddecimalscale value0 to 6
icpart1/2Parental feelings total scale, child self-reported, 0-14 childderiveddecimalscale value0 to 14
icpasci1/2Science Perceived Ability scale, Child-self-rated at 9 (1-5)childderiveddecimalscale value 1 to 5
icpLLCageAge of twin when 9yr parent and child booklets completed (for use in LLC TRE), months parentderivedintegerquantitative approx. 102 to 118 (months)
icpLLCdateDate when 9yr parent and child booklets completed (for use in LLC TRE), yyyy-mm string parentderivedstringdate value approx. '2003-03' to '2004-07'
icpuz011/2Puzzle Quiz item 1 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz031/2Puzzle Quiz item 3 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz041/2Puzzle Quiz item 4 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz051/2Puzzle Quiz item 5 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz061/2Puzzle Quiz item 6 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz071/2Puzzle Quiz item 7 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz081/2Puzzle Quiz item 8 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz091/2Puzzle Quiz item 9 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz101/2Puzzle Quiz item 10 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz111/2Puzzle Quiz item 11 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz121/2Puzzle Quiz item 12 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz131/2Puzzle Quiz item 13 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz141/2Puzzle Quiz item 14 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz151/2Puzzle Quiz item 15 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz161/2Puzzle Quiz item 16 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz171/2Puzzle Quiz item 17 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz181/2Puzzle Quiz item 18 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz191/2Puzzle Quiz item 19 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz201/2Puzzle Quiz item 20 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz211/2Puzzle Quiz item 21 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz221/2Puzzle Quiz item 22 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz231/2Puzzle Quiz item 23 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuz241/2Puzzle Quiz item 24 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icpuzt1/2Puzzle test total score (child at 9), 0-23 childderivedintegerscale value0 to 23
icsdqbeht1/2SDQ Behaviour Problems total (child self-report) at 9, 0-40childderiveddecimalscale value 0 to 40
icsdqcon11/2Behaviour: get very angry (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqcon21/2Behaviour: do as I am told (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqcon2r1/2Reversed version of icsdqcon2, see value labelschilditemintegerordinal0=very true, 1=quite true, 2=not true
icsdqcon31/2Behaviour: fight a lot (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqcon41/2Behaviour: lying or cheating (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqcon51/2Behaviour: I take things not mine (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqcont1/2SDQ Conduct scale (child self-report) at 9, 0-10 childderiveddecimalscale value0 to 10
icsdqemo11/2Behaviour: get a lot of headaches (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqemo21/2Behaviour: worry a lot (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqemo31/2Behaviour: often unhappy (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqemo41/2Behaviour: nervous in new situations (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqemo51/2Behaviour: have many fears (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqemot1/2SDQ Emotion scale (child self-report) at 9, 0-10 childderiveddecimalscale value0 to 10
icsdqhyp11/2Behaviour: jumpy (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqhyp21/2Behaviour: fidgeting or squirming (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqhyp31/2Behaviour: easily distracted (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqhyp41/2Behaviour: think before I act (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqhyp4r1/2Reversed version of icsdqhyp4, see value labelschilditemintegerordinal0=very true, 1=quite true, 2=not true
icsdqhyp51/2Behaviour: finish my work (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqhyp5r1/2Reversed version of icsdqhyp5, see value labelschilditemintegerordinal0=very true, 1=quite true, 2=not true
icsdqhypt1/2SDQ Hyperactivity scale (child self-report) at 9, 0-10childderiveddecimalscale value 0 to 10
icsdqper11/2Behaviour: usually on my own (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqper21/2Behaviour: one or more good friends (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqper2r1/2Reversed version of icsdqper2, see value labelschilditemintegerordinal0=very true, 1=quite true, 2=not true
icsdqper31/2Behaviour: liked by others my age (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqper3r1/2Reversed version of icsdqper3, see value labelschilditemintegerordinal0=very true, 1=quite true, 2=not true
icsdqper41/2Behaviour: other children pick on me (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqper51/2Behaviour: get on better with adults (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqpert1/2SDQ Peer Problem scale (child self-report) at 9, 0-10 childderiveddecimalscale value0 to 10
icsdqpro11/2Behaviour: try to be nice (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqpro21/2Behaviour: like to share with others (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqpro31/2Behaviour: helpful if someone hurt (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqpro41/2Behaviour: kind to younger children (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqpro51/2Behaviour: often volunteer (child at 9), see value labelschilditemintegerordinal0=not true, 1=quite true, 2=very true
icsdqprot1/2SDQ Prosocial scale (child self-report) at 9, 0-10 childderiveddecimalscale value0 to 10
icshp021/2Shapes Quiz item 2 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp031/2Shapes Quiz item 3 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp041/2Shapes Quiz item 4 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp051/2Shapes Quiz item 5 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp061/2Shapes Quiz item 6 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp071/2Shapes Quiz item 7 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp081/2Shapes Quiz item 8 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp091/2Shapes Quiz item 9 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp101/2Shapes Quiz item 10 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp111/2Shapes Quiz item 11 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp121/2Shapes Quiz item 12 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp131/2Shapes Quiz item 13 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp141/2Shapes Quiz item 14 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp151/2Shapes Quiz item 15 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp161/2Shapes Quiz item 16 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp171/2Shapes Quiz item 17 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp181/2Shapes Quiz item 18 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp191/2Shapes Quiz item 19 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp201/2Shapes Quiz item 20 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp211/2Shapes Quiz item 21 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp221/2Shapes Quiz item 22 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp231/2Shapes Quiz item 23 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshp241/2Shapes Quiz item 24 score (child at 9), 1right 0wrong childderivedintegerordinal0=incorrect, 1=correct
icshpt1/2Shapes test total score (child at 9), 0-23 childderivedintegerscale value0 to 23
icvb1/2Verbal composite (9 year child), standardised childderiveddecimalscale valueapprox. -3 to +3 (standardized)
icwrd011/2Word Quiz item 1 score (child at 9), 2best answer 0wrongchildderivedintegerordinal 0=incorrect, 2=correct
icwrd021/2Word Quiz item 2 score (child at 9), 2best answer 0wrongchildderivedintegerordinal 0=incorrect, 2=correct
icwrd031/2Word Quiz item 3 score (child at 9), 2best answer 0wrongchildderivedintegerordinal 0=incorrect, 2=correct
icwrd041/2Word Quiz item 4 score (child at 9), 2best answer 0wrongchildderivedintegerordinal 0=incorrect, 2=correct
icwrd051/2Word Quiz item 5 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd061/2Word Quiz item 6 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd071/2Word Quiz item 7 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd081/2Word Quiz item 8 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd091/2Word Quiz item 9 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd101/2Word Quiz item 10 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd111/2Word Quiz item 11 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd121/2Word Quiz item 12 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd131/2Word Quiz item 13 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd141/2Word Quiz item 14 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd151/2Word Quiz item 15 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd161/2Word Quiz item 16 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd171/2Word Quiz item 17 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd181/2Word Quiz item 18 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd191/2Word Quiz item 19 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrd201/2Word Quiz item 20 score (child at 9), 2best answer 1other correct answer 0wrongchildderivedinteger ordinal0=incorrect, 1=partly correct, 2=correct
icwrdh1/2Word Quiz, parent helped twin read questions (child at 9), 1Y 0Nchilditemintegernominal 0=no, 1=yes
icwrdt1/2Word/vocabulary test total score (child at 9), 0-40 childderivedintegerscale value0 to 40
inineyr9 Year data present, 1Y 0Nparent, child, teacherderivedintegernominal0=no, 1=yes
ipanx011/2Behaviour: afraid of closed spaces etc (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx021/2Behaviour: slow to warm to strangers (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx031/2Behaviour: afraid social situations (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx041/2Behaviour: checks things done right (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx051/2Behaviour: asks for reassurance (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx061/2Behaviour: insists on doing things over (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx071/2Behaviour: shy or timid (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx081/2Behaviour: afraid of medical procedures (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx091/2Behaviour: twitches or mannerisms (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx101/2Behaviour: does not enjoy self (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx111/2Behaviour: critical of self (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx121/2Behaviour: complains or whines (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx131/2Behaviour: low self confidence (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx141/2Behaviour: fussy (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx151/2Behaviour: blames self (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx161/2Behaviour: upset when parent leaves (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx171/2Behaviour: keyed up or on edge (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx181/2Behaviour: afraid of animals (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx191/2Behaviour: anxious (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanx201/2Behaviour: resists sleeping alone (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipanxfeart1/2ARBQ fear total (9 year parent), 0-10parentderiveddecimalscale0 to 10
ipanxnafft1/2ARBQ negative affect total (9 year parent), 0-10parentderiveddecimalscale0 to 10
ipanxncogt1/2ARBQ negative cognition total (9 year parent), 0-12parentderiveddecimalscale0 to 12
ipanxocbt1/2ARBQ OCB total (9 year parent), 0-6parentderiveddecimalscale0 to 6
ipanxshyt1/2ARBQ shyness (social anxiety) total (9 year parent), 0-8parentderiveddecimalscale0 to 8
ipanxt1/2ARBQ overall anxiety total (9 year parent), 0-50parentderiveddecimalscale0 to 50
ipaps011/2Behaviour: blames others for mistakes (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps021/2Behaviour: illegal activities (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps031/2Behaviour: concerned about school progress (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps03r1/2Reversed version of ipaps031, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipaps041/2Behaviour: acts without thinking (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps051/2Behaviour: shallow emotions (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps061/2Behaviour: lies easily (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps071/2Behaviour: keeps promises (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps07r1/2Reversed version of ipaps071, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipaps081/2Behaviour: brags excessively (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps091/2Behaviour: gets bored easily (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps101/2Behaviour: uses other people (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps111/2Behaviour: teases (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps121/2Behaviour: feels guilty when done wrong (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps12r1/2Reversed version of ipaps121, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipaps131/2Behaviour: risky activities (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps141/2Behaviour: superficially charming (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps151/2Behaviour: angry when corrected (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps161/2Behaviour: thinks is more important (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps171/2Behaviour: does not plan ahead (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps181/2Behaviour: concerned about feelings (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps18r1/2Reversed version of ipaps181, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipaps191/2Behaviour: does not show feelings (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps201/2Behaviour: keeps the same friends (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipaps20r1/2Reversed version of ipaps201, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipapscalt1/2APSD Callous-Unemotional scale (parent), 0-12 teacherderiveddecimalscale value0 to 12
ipapsdt1/2APSD overall total scale (parent), 0-40teacher deriveddecimalscale value0 to 40
ipapsecalt1/2APDS Enhanced Callous-Unemotional scale (parent), 0-16teacherderiveddecimalscale value0 to 16
ipapsimpt1/2APSD Impulsivity scale (parent), 0-10 teacherderiveddecimalscale value0 to 10
ipapsnart1/2APSD Narcissism scale (parent), 0-14 teacherderiveddecimalscale value0 to 14
ipasthm1/2Twin has Asthma (parent at 9), 1Y 0Nparent itemintegernominal0=no, 1=yes
ipbpalo1/2Being a Parent: wish child would leave alone (parent at 9), see value labelsparentiteminteger ordinal0=rarely or never, 1=sometimes, 2=often
ipbpamr1/2Reversed version of ipbpamu1, see value labels parentitemintegerordinal0=often, 1=sometimes, 2=rarely or never
ipbpamu1/2Being a Parent: feel amused by child (parent at 9), see value labelsparentitemintegerordinal 0=rarely or never, 1=sometimes, 2=often
ipbpang1/2Being a Parent: child makes me angry (parent at 9), see value labelsparentitemintegerordinal 0=rarely or never, 1=sometimes, 2=often
ipbpclo1/2Being a Parent: feel close to child (parent at 9), see value labelsparentitemintegerordinal 0=rarely or never, 1=sometimes, 2=often
ipbpclr1/2Reversed version of ipbpclo1, see value labels parentitemintegerordinal0=often, 1=sometimes, 2=rarely or never
ipbpeat1/2Being a Parent: days per week child eats evening meal with parent (parent at 9), 0-7parentiteminteger quantitative0 to 7
ipbpfru1/2Being a Parent: feel frustrated by child (parent at 9), see value labelsparentiteminteger ordinal0=rarely or never, 1=sometimes, 2=often
ipbphap1/2Being a Parent: happy about relationship with child (parent at 9), see value labelsparentiteminteger ordinal0=rarely or never, 1=sometimes, 2=often
ipbphar1/2Reversed version of ipbphap1, see value labels parentitemintegerordinal0=often, 1=sometimes, 2=rarely or never
ipbpimp1/2Being a Parent: feel impatient with child (parent at 9), see value labelsparentiteminteger ordinal0=rarely or never, 1=sometimes, 2=often
ipbpsle1/2Being a Parent: hours of sleep child gets per school night (parent at 9), see value labelsparentitem integerordinal1=6 or less, 2=7, 3=8, 4=9, 5=10, 6=11 or more
ipcacce1/2CEQ Acceptance (parent) mean scale at 9, 0-2 parentderiveddecimalscale value0 to 2
ipcadve1/2CEQ Adventure (parent) mean scale at 9, 0-2 parentderiveddecimalscale value0 to 2
ipcas011/2Behaviour: wants to fit in with peers (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas01r1/2Reversed version of ipcas011, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipcas021/2Behaviour: odd communication style (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas031/2Behaviour: interest in unusual topic (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas041/2Behaviour: one-sided social behaviour (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas051/2Behaviour: can keep conversation going (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas05r1/2Reversed version of ipcas051, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipcas061/2Behaviour: same interests as peers (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas06r1/2Reversed version of ipcas061, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipcas071/2Behaviour: unusual movements (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas081/2Behaviour: unusual memory for details (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas091/2Behaviour: tactless (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas101/2Behaviour: turns conversations (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas111/2Behaviour: loses the listener (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas131/2Behaviour: likes to do things over (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas141/2Behaviour: prefers imaginative activities (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas161/2Behaviour: unusual eye gaze (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas171/2Behaviour: interacts easily children (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas17r1/2Reversed version of ipcas171, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipcas181/2Behaviour: people are important (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas18r1/2Reversed version of ipcas181, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipcas191/2Behaviour: cares how perceived by group (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcas19r1/2Reversed version of ipcas191, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipcas201/2Behaviour: takes things literally (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcascomt1/2CAST Communication scale at 9 (parent), 0-14 parentderiveddecimalscale value0 to 14
ipcasnont1/2CAST Non-Social scale at 9 (parent), 0-10 parentderiveddecimalscale value0 to 10
ipcassoct1/2CAST Social scale at 9 (parent), 0-14parent deriveddecimalscale value0 to 14
ipcastt1/2CAST overall total at 9 (parent), 0-38parent deriveddecimalscale value0 to 38
ipchaos1rReversed version of ipchaos1x, see value labels parentitemintegerordinal0=certainly true, 1=somewhat true, 2=not true
ipchaos1xHome: regular bedtime routine (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipchaos2xHome: cannot hear yourself think (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipchaos3xHome: a real zoo (parent at 9), see value labels parentitemintegerordinal0=not true, 1=somewhat true, 2=certainly true
ipchaos4rReversed version of ipchaos4x, see value labels parentitemintegerordinal0=certainly true, 1=somewhat true, 2=not true
ipchaos4xHome: we stay on top of things (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipchaos5xHome: usually a TV on (parent at 9), see value labels parentitemintegerordinal0=not true, 1=somewhat true, 2=certainly true
ipchaos6rReversed version of ipchaos6x, see value labels parentitemintegerordinal0=certainly true, 1=somewhat true, 2=not true
ipchaos6xHome: calm atmosphere (parent at 9), see value labels parentitemintegerordinal0=not true, 1=somewhat true, 2=certainly true
ipchatotParent Chaos scale at 9, 0-12parent deriveddecimalscale value0 to 12
ipcla011/2Twin classroom: likes to be (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcla021/2Twin classroom: accepted by other children (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
ipcla031/2Twin classroom: work will help in future (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
ipcla041/2Twin classroom: feels upset (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcla051/2Twin classroom: work is interesting (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcla061/2Twin classroom: friends care about work (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
ipcla071/2Twin classroom: teacher takes an interest (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
ipcla081/2Twin classroom: feels unhappy (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcla091/2Twin classroom: gets on well with children (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
ipcla101/2Twin classroom: has fun (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcla111/2Twin classroom: gets excited about work (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
ipcla121/2Twin classroom: learning will help in 2ndary (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
ipcla131/2Twin classroom: feels lonely (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcla141/2Twin classroom: teacher treates fairly (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcla151/2Twin classroom: likes to do extra work (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcla161/2Twin classroom: friends try their best (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcla171/2Twin classroom: teacher helps to do best (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
ipcla181/2Twin classroom: feels worried (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcla191/2Twin classroom: learns things they care about (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
ipcla201/2Twin classroom: friends enjoy learning (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcla211/2Twin classroom: teacher listens (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcla221/2Twin classroom: feels happy (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcla231/2Twin classroom: people think a lot of (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcla241/2Twin classroom: learning will be useful (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
ipcla251/2Twin classroom: feels proud to be a pupil (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
ipcla261/2Twin classroom: friends often in trouble (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
ipcla271/2Twin classroom: popular with other children (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
ipcla281/2Twin classroom: learning is fun (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
ipcnega1/2CEQ Negative Affect (parent) mean scale at 9, 0-2 parentderiveddecimalscale value0 to 2
ipcoga11/2Behaviour: clever (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcoga21/2Behaviour: can solve problems (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcoga31/2Behaviour: finds learning easy (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipcom011/2Communication: people can understand (parent at 9), see value labelsparentitemintegernominal 0=not true, 1=somewhat true, 2=certainly true
ipcom021/2Communication: rarely makes mistakes (parent at 9), see value labelsparentitemintegernominal 0=not true, 1=somewhat true, 2=certainly true
ipcom031/2Communication: speech sounds like younger (parent at 9), see value labelsparentiteminteger nominal0=not true, 1=somewhat true, 2=certainly true
ipcom041/2Communication: sentences harder to understand (parent at 9), see value labelsparentiteminteger nominal0=not true, 1=somewhat true, 2=certainly true
ipcom051/2Communication: speech is 2 or 3 word phrases (parent at 9), see value labelsparentiteminteger nominal0=not true, 1=somewhat true, 2=certainly true
ipcom061/2Communication: can say long sentences (parent at 9), see value labelsparentitemintegernominal 0=not true, 1=somewhat true, 2=certainly true
ipcom071/2Communication: leaves out words and endings (parent at 9), see value labelsparentiteminteger nominal0=not true, 1=somewhat true, 2=certainly true
ipcom081/2Communication: makes mistakes on pronouns (parent at 9), see value labelsparentiteminteger nominal0=not true, 1=somewhat true, 2=certainly true
ipcom091/2Communication: can give easy-to-follow account (parent at 9), see value labelsparentiteminteger nominal0=not true, 1=somewhat true, 2=certainly true
ipcom101/2Communication: can talk clearly about future (parent at 9), see value labelsparentiteminteger nominal0=not true, 1=somewhat true, 2=certainly true
ipcom111/2Communication: finds it hard to tell story (parent at 9), see value labelsparentiteminteger nominal0=not true, 1=somewhat true, 2=certainly true
ipcom121/2Communication: uses words like he or it (parent at 9), see value labelsparentiteminteger nominal0=not true, 1=somewhat true, 2=certainly true
ipcoppo1/2CEQ Opportunity (parent) mean scale at 9, 0-2 parentderiveddecimalscale value0 to 2
ipcpeer1/2CEQ Friends/Peer Context (parent) mean scale at 9, 0-2parentderiveddecimalscale value 0 to 2
ipcsati1/2CEQ Classroom Satisfaction (parent) mean scale at 9, 0-2parentderiveddecimalscale value 0 to 2
ipcteac1/2CEQ Teachers (parent) mean scale at 9, 0-2 parentderiveddecimalscale value0 to 2
ipdadldDad had learning difficulties (parent at 9), see value labelsparentitemintegernominal 1=talking or language problems, 2=reading problems, 3=both, 4=neither
ipdataParent booklet data present at 9, 1Y 0Nparent itemintegernominal0=no, 1=yes
ipdiask1/2Discipline: ask someone else (parent at 9), see value labelsparentitemintegerordinal 0=rarely or never, 1=sometimes, 2=often
ipdiexp1/2Discipline: explain or reason (parent at 9), see value labelsparentitemintegerordinal 0=rarely or never, 1=sometimes, 2=often
ipdiexr1/2Reversed version of ipdiexp1, see value labels parentitemintegerordinal0=often, 1=sometimes, 2=rarely or never
ipdifir1/2Discipline: be firm or calm (parent at 9), see value labelsparentitemintegerordinal 0=rarely or never, 1=sometimes, 2=often
ipdifrr1/2Reversed version of ipdifir1, see value labels parentitemintegerordinal0=often, 1=sometimes, 2=rarely or never
ipdijok1/2Discipline: make a joke (parent at 9), see value labelsparentitemintegerordinal 0=rarely or never, 1=sometimes, 2=often
ipdisavot1/2Parental discipline avoidance scale, parent-reported, 0-4 parentderiveddecimalscale value0 to 4
ipdisho1/2Discipline: shout or tell off (parent at 9), see value labelsparentitemintegerordinal 0=rarely or never, 1=sometimes, 2=often
ipdisma1/2Discipline: smack (parent at 9), see value labels parentitemintegerordinal0=rarely or never, 1=sometimes, 2=often
ipdisnegt1/2Parental discipline negative/harsh scale, parent-reported, 0-4 parentderiveddecimalscale value0 to 4
ipdispost1/2Parental discipline positive scale, parent-reported, 0-4 parentderiveddecimalscale value0 to 4
ipeczem1/2Twin has Eczema (parent at 9), 1Y 0Nparent itemintegernominal0=no, 1=yes
ipemi11/2Behaviour: makes most of tedious tasks (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipemi21/2Behaviour: likes to use brain (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipemi31/2Behaviour: takes criticism (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipemi41/2Behaviour: puts in more effort to improve (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipemi51/2Behaviour: fun is more important (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipfinchangeMajor financial changes over last two years (parent at 9), see value labelsparentitemintegernominal 0=no, 1=yes but same financial situation now, 2=yes finances now worse, 3=yes finances now better
ipfooal1/2Twin has Other Food Allergy (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
ipgoo011/2Good at reading (parent at 9), see value labels parentitemintegerordinal1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
ipgoo021/2Good at writing (parent at 9), see value labels parentitemintegerordinal1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
ipgoo031/2Good at spelling (parent at 9), see value labels parentitemintegerordinal1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
ipgoo041/2Good at solving number problems (parent at 9), see value labelsparentitemintegerordinal 1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
ipgoo051/2Good at mental arithmetic (parent at 9), see value labelsparentitemintegerordinal 1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
ipgoo061/2Good at multiplying and dividing (parent at 9), see value labelsparentitemintegerordinal 1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
ipgoo071/2Good at learning about nature (parent at 9), see value labelsparentitemintegerordinal 1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
ipgoo081/2Good at testing things out (parent at 9), see value labelsparentitemintegerordinal 1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
ipgoo091/2Good at finding out how things work (parent at 9), see value labelsparentitemintegerordinal 1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
ipgoo101/2Good at team games (parent at 9), see value labels parentitemintegerordinal1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
ipgoo111/2Good at races and competitions (parent at 9), see value labelsparentitemintegerordinal 1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
ipgoo121/2Good at PE classes (parent at 9), see value labels parentitemintegerordinal1=very good, 2=quite good, 3=doing OK, 4=not so good, 5=not at all good
iphayfv1/2Twin has Hayfever (parent at 9), 1Y 0Nparent itemintegernominal0=no, 1=yes
iphom011/2Home: make sure child sets aside HW time (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
iphom021/2Home: TV is on when child doing HW (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iphom031/2Home: help with HW when needed (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iphom041/2Home: help with HW should be done alone (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
iphom051/2Home: nights per week HW is set (parent at 9), see value labelsparentitemintegerordinal 0=0, 1=1, 2=2, 3=3, 4=4, 5=5 or more
iphom061/2Home: hours per night spent on HW (parent at 9), see value labelsparentitemintegerordinal 0=half or less, 1=1, 2=2, 3=3 or more
iphom07XHome: good education is important (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iphom08XHome: important to do best in school (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iphom091/2Home: discuss school activities with child (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
iphom101/2Home: interested in school marks (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iphom171/2Home: child reads for fun (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iphom181/2Home: I often read to child (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iphom191/2Home: child taken to museum in last year (parent at 9), see value labelsparentiteminteger ordinal0=not true, 1=somewhat true, 2=certainly true
iphom201/2Home: computer at home used by child (parent at 9), see value labelsparentitemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
iphom21XHome: how many books (parent at 9), see value labels parentitemintegerordinal1=0-10, 2=11-25, 3=26-50, 4=51-99, 5=100 or more
iphom221/2Home: hours of TV watched per school day (parent at 9), see value labelsparentiteminteger ordinal0=0, 1=1, 2=2, 3=3, 4=4, 5=5 or more
iphom231/2Home: hours of TV watched per weekend day (parent at 9), see value labelsparentiteminteger ordinal0=0, 1=1, 2=2, 3=3, 4=4, 5=5 or more
ipincomeHousehold income (parent at 9), see value labels parentitemintegerordinal1=under £4500, 2=£4500-9499, 3=£9500-15499, 4=£15500-17499, 5=£17500-24999, 6=£25000-29999, 7=£30000-39999, 8=£40000-49999, 9=£50000-74999, 10=£75000-99999, 11=£100000 or more
ipintrntInternet access at home (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
ipldaut1/2Twin learning difficulty: Autism or Aspergers (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
iplddsl1/2Twin learning difficulty: Dyslexia/Reading (parent at 9), 1Y 0Nparentitemintegernominal 0=no, 1=yes
iplddsp1/2Twin learning difficulty: Dyspraxia/Motor Skills (parent at 9), 1Y 0Nparentiteminteger nominal0=no, 1=yes
ipldeye1/2Twin learning difficulty: Eyesight (parent at 9), 1Y 0Nparentitemintegernominal0=no, 1=yes
ipldfal1/2Twin learning difficulty: Falling behind at school (parent at 9), 1Y 0Nparentiteminteger nominal0=no, 1=yes
ipldhea1/2Twin learning difficulty: Hearing (parent at 9), 1Y 0Nparentitemintegernominal0=no, 1=yes
ipldhyp1/2Twin learning difficulty: Hyperactivity/ADHD (parent at 9), 1Y 0Nparentitemintegernominal 0=no, 1=yes
ipldlan1/2Twin learning difficulty: Language/Speech (parent at 9), 1Y 0Nparentitemintegernominal 0=no, 1=yes
ipldmth1/2Twin learning difficulty: Maths (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
ipldrst1/2Twin learning difficulty: Restless/Concentration (parent at 9), 1Y 0Nparentiteminteger nominal0=no, 1=yes
ipldspl1/2Twin learning difficulty: Spelling (parent at 9), 1Y 0Nparentitemintegernominal0=no, 1=yes
ipldwri1/2Twin learning difficulty: Writing (parent at 9), 1Y 0Nparentitemintegernominal0=no, 1=yes
iplebirsLife Event: Birth of Younger Sibling (parent at 9), 1Y 0Nparentitemintegernominal0=no, 1=yes
iplebcountCount of reported life events (9 year parent), 0-6parent derivedintegerordinal0 to 6
ipledivpLife Event: Divorce/Separation of Parents (parent at 9), 1Y 0Nparentitemintegernominal 0=no, 1=yes
ipledthgLife Event: Death of Grandparent (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
ipledthoLife Event: Death of Other Relative/Friend (parent at 9), 1Y 0Nparentitemintegernominal 0=no, 1=yes
iplefindLife Event: unemployment or financial difficulties (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
iplehos1/2Life Event: Hospitalisation of twin (parent at 9), 1Y 0Nparentitemintegernominal 0=no, 1=yes
iplehospLife Event: Hospitalisation of Parent (parent at 9), 1Y 0Nparentitemintegernominal0=no, 1=yes
iplehossLife Event: Hospitalisation of Sibling (parent at 9), 1Y 0Nparentitemintegernominal 0=no, 1=yes
ipleillrLife Event: Illness/Injury of Relative/Friend (parent at 9), 1Y 0Nparentitemintegernominal 0=no, 1=yes
iplemovhLife Event: Moved House (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
iplenewcLife Event: New Child (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
iplenewpLife Event: New Parent Figure (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
ipleothLife Event: other categories (parent at 9), see value labelsparent itemintegernominal0=no, 1=family member moved away, 2=death of pet, 3=bullying or harrassment
ipleseppLife Event: Prolonged Separation from Parent (parent at 9), 1Y 0Nparentitemintegernominal 0=no, 1=yes
iplhadltOther adults living in household (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
iplhgndpGrandparent living in household (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
iplhlenOther adult length of time in household (parent at 9), see value labelsparentitemintegerordinal 1=under 1 year, 2=1 to 4 years, 3=over 4 years
iplhnannNanny/au pair living in household (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
iplhorelOther relative living in household (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
iplhothrOther category of adult living in household (parent at 9), 1Y 0Nparentitemintegernominal 0=no, 1=yes
ipliaca1/2Academic Liking scale, Parent-rated at 9 (1-5) parentderiveddecimalscale value1 to 5
iplieng1/2English Liking scale, Parent-rated at 9 (1-5) parentderiveddecimalscale value1 to 5
iplik011/2Likes reading (parent at 9), see value labels parentitemintegerordinal1=likes it very much, 2=does like it, 3=think it's OK, 4=doesn't like it at all, 5=dislikes it very much
iplik021/2Likes writing (parent at 9), see value labels parentitemintegerordinal1=likes it very much, 2=does like it, 3=think it's OK, 4=doesn't like it at all, 5=dislikes it very much
iplik031/2Likes spelling (parent at 9), see value labels parentitemintegerordinal1=likes it very much, 2=does like it, 3=think it's OK, 4=doesn't like it at all, 5=dislikes it very much
iplik041/2Likes solving number problems (parent at 9), see value labelsparentitemintegerordinal 1=likes it very much, 2=does like it, 3=think it's OK, 4=doesn't like it at all, 5=dislikes it very much
iplik051/2Likes mental arithmetic (parent at 9), see value labelsparentitemintegerordinal 1=likes it very much, 2=does like it, 3=think it's OK, 4=doesn't like it at all, 5=dislikes it very much
iplik061/2Likes multiplying and dividing (parent at 9), see value labelsparentitemintegerordinal 1=likes it very much, 2=does like it, 3=think it's OK, 4=doesn't like it at all, 5=dislikes it very much
iplik071/2Likes learning about nature (parent at 9), see value labelsparentitemintegerordinal 1=likes it very much, 2=does like it, 3=think it's OK, 4=doesn't like it at all, 5=dislikes it very much
iplik081/2Likes testing things out (parent at 9), see value labelsparentitemintegerordinal 1=likes it very much, 2=does like it, 3=think it's OK, 4=doesn't like it at all, 5=dislikes it very much
iplik091/2Likes finding out how things work (parent at 9), see value labelsparentitemintegerordinal 1=likes it very much, 2=does like it, 3=think it's OK, 4=doesn't like it at all, 5=dislikes it very much
iplik101/2Likes team games (parent at 9), see value labels parentitemintegerordinal1=likes it very much, 2=does like it, 3=think it's OK, 4=doesn't like it at all, 5=dislikes it very much
iplik111/2Likes races and competitions (parent at 9), see value labelsparentitemintegerordinal 1=likes it very much, 2=does like it, 3=think it's OK, 4=doesn't like it at all, 5=dislikes it very much
iplik121/2Likes PE classes (parent at 9), see value labels parentitemintegerordinal1=likes it very much, 2=does like it, 3=think it's OK, 4=doesn't like it at all, 5=dislikes it very much
iplimat1/2Maths Liking scale, Parent-rated at 9 (1-5) parentderiveddecimalscale value1 to 5
ipliphy1/2Physical Education Liking scale, Parent-rated at 9 (1-5)parentderiveddecimalscale value 1 to 5
iplisci1/2Science Liking scale, Parent-rated at 9 (1-5) parentderiveddecimalscale value1 to 5
iplndif1/2Twin has Learning Difficulties (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
ipmaristYour marital status (parent at 9), see value labels parentitemintegernominal 1=married to natural parent, 2=married to other, 3=cohabiting with natural parent, 4=cohabiting with other, 5=single separated, 6=single divorced, 7=single never married, 8=single widowed
ipmgfldMaternal Grandfather had learning difficulties (parent at 9), see value labelsparentiteminteger nominal1=talking or language problems, 2=reading problems, 3=both, 4=neither
ipmgmldMaternal Grandmother had learning difficulties (parent at 9), see value labelsparentiteminteger nominal1=talking or language problems, 2=reading problems, 3=both, 4=neither
ipmoaca1/2Academic Overall Motivational scale, Parent-rated at 9 (1-5)parentderiveddecimalscale value 1 to 5
ipmumldMum had learning difficulties (parent at 9), see value labelsparentitemintegernominal 1=talking or language problems, 2=reading problems, 3=both, 4=neither
ipnutal1/2Twin has Nut Allergy (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
ipodd11/2Behaviour: argues with adults (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipodd31/2Behaviour: deliberately annoys (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipodd41/2Behaviour: touchy (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipodd51/2Behaviour: angry and resentful (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipodd61/2Behaviour: spiteful or vindictive (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipoddt1/2ODD total scale (parent at 9), 0-10parentderiveddecimalscale0 to 10
iposbldOlder Sibling Brother had learning difficulties (parent at 9), see value labelsparentiteminteger nominal1=talking or language problems, 2=reading problems, 3=both, 4=neither
ipossldOlder Sibling Sister had learning difficulties (parent at 9), see value labelsparentiteminteger nominal1=talking or language problems, 2=reading problems, 3=both, 4=neither
ipothal1/2Twin has Any Other Allergies (parent at 9), see value labels parentitemintegernominal0=no, 1=antibiotics, 2=animals or fur, 3=other skin contact, 9=miscellaneous other
ippaaca1/2Academic Perceived Ability scale, Parent-rated at 9 (1-5)parentderiveddecimalscale value 1 to 5
ippaeng1/2English Perceived Ability scale, Parent-rated at 9 (1-5)parentderiveddecimalscale value 1 to 5
ippag11/2Behaviour: uses physical force (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ippag21/2Behaviour: threatens others (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ippag31/2Behaviour: gets others to gang up (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ippagt1/2Proactive Aggression scale (parent), 0-6 teacherderiveddecimalscale value0 to 6
ippamat1/2Maths Perceived Ability scale, Parent-rated at 9 (1-5)parentderiveddecimalscale value 1 to 5
ippaphy1/2Physical Education Perceived Ability scale, Parent-rated at 9 (1-5)parentderiveddecimal scale value1 to 5
ipparlenPartner length of time with family (parent at 9), see value labelsparentitemintegerordinal 1=under 6 months, 2=6 months to 1 year, 3=1 to 2 years, 4=2 to 3 years, 5=3 to 4 years, 6=over 4 years
ipparnegt1/2Negative parental feelings scale, parent-rated at 9, 0-8 parentderiveddecimalscale value0 to 8
ipparpost1/2Positive parental feelings scale, parent-rated at 9, 0-6 parentderiveddecimalscale value0 to 6
ipparrelPartner relationship to twins (parent at 9), see value labelsparentitemintegernominal 0=other, 1=birth mother, 2=natural father, 3=stepmother, 4=stepfather, 5=foster mother, 6=foster father, 7=grandmother, 8=grandfather
ippart1/2Parental feelings total scale, Parent-reported, 0-14 parentderiveddecimalscale value0 to 14
ippartnrCurrently live with a partner (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
ippasci1/2Science Perceived Ability scale, Parent-rated at 9 (1-5)parentderiveddecimalscale value 1 to 5
ippgfldPaternal Grandfather had learning difficulties (parent at 9), see value labelsparentiteminteger nominal1=talking or language problems, 2=reading problems, 3=both, 4=neither
ippgmldPaternal Grandmother had learning difficulties (parent at 9), see value labelsparentiteminteger nominal1=talking or language problems, 2=reading problems, 3=both, 4=neither
iprag11/2Behaviour: blames others in fights (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
iprag21/2Behaviour: strikes back when teased (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
iprag31/2Behaviour: overreacts angrily (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipragt1/2Reactive Aggression scale (parent), 0-6 teacherderiveddecimalscale value0 to 6
iprelatYour relationship to twins (parent at 9), see value labelsparentitemintegernominal 0=other, 1=birth mother, 2=natural father, 3=stepmother, 4=stepfather, 5=foster mother, 6=foster father, 7=grandmother, 8=grandfather
iprelldlangNumber of reported relatives with language problems, see value labels parentderivedintegerordinal0, 1, 2, 3, 4=4-6, 5=7-10
iprelldreadNumber of reported relatives with reading problems, see value labels parentderivedintegerordinal0, 1, 2, 3, 4=4-6, 5=7-10
ipsdqbeht1/2SDQ Behaviour Problems total (parent) at 9, 0-40 parentderiveddecimalscale value0 to 40
ipsdqcon11/2Behaviour: temper tantrums (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqcon21/2Behaviour: obedient (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqcon2r1/2Reversed version of ipsdqcon21, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipsdqcon31/2Behaviour: fights or bullies (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqcon41/2Behaviour: often lies or cheats (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqcon51/2Behaviour: steals (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqcont1/2SDQ Conduct scale (parent) at 9, 0-10parent deriveddecimalscale value0 to 10
ipsdqemo11/2Behaviour: complains of headaches (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqemo21/2Behaviour: many worries (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqemo31/2Behaviour: often unhappy (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqemo41/2Behaviour: nervous or clingy (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqemo51/2Behaviour: many fears (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqemot1/2SDQ Emotion scale (parent) at 9, 0-10parent deriveddecimalscale value0 to 10
ipsdqhyp11/2Behaviour: restless (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqhyp21/2Behaviour: fidgets or squirms (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqhyp31/2Behaviour: easily distracted (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqhyp41/2Behaviour: thinks before acting (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqhyp4r1/2Reversed version of ipsdqhyp41, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipsdqhyp51/2Behaviour: sees tasks through to end (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqhyp5r1/2Reversed version of ipsdqhyp51, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipsdqhypt1/2SDQ Hyperactivity scale (parent) at 9, 0-10 parentderiveddecimalscale value0 to 10
ipsdqper11/2Behaviour: solitary (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqper21/2Behaviour: has at least one good friend (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqper2r1/2Reversed version of ipsdqper21, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipsdqper31/2Behaviour: generally liked (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqper3r1/2Reversed version of ipsdqper31, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipsdqper41/2Behaviour: picked on by other children (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqper51/2Behaviour: gets on better with adults (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqpert1/2SDQ Peer Problem scale (parent) at 9, 0-10 parentderiveddecimalscale value0 to 10
ipsdqpro11/2Behaviour: considerate (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqpro21/2Behaviour: shares with other children (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqpro31/2Behaviour: helpful if someone hurt (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqpro3r1/2Reversed version of ipsdqpro31, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipsdqpro41/2Behaviour: kind to younger children (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqpro4r1/2Reversed version of ipsdqpro41, see value labelsparentitemintegerordinal0=very true, 1=quite true, 2=not true
ipsdqpro51/2Behaviour: volunteers to help others (parent at 9), see value labelsparentitemintegerordinal0=not true, 1=quite true, 2=very true
ipsdqprot1/2SDQ Prosocial scale (parent) at 9, 0-10 parentderiveddecimalscale value0 to 10
ipsen1/2Twin has Statement of SEN (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
ipsenrg1/2Twin is on SEN Register (parent at 9), 1Y 0N parentitemintegernominal0=no, 1=yes
ipysbldYounger Sibling Brother had learning difficulties (parent at 9), see value labelsparentiteminteger nominal1=talking or language problems, 2=reading problems, 3=both, 4=neither
ipyssldYounger Sibling Sister had learning difficulties (parent at 9), see value labelsparentiteminteger nominal1=talking or language problems, 2=reading problems, 3=both, 4=neither
isameschTwins at the same school at 9 (from admin database), 1Y 0Nadminitemintegernominal0=no, 1=yes
isametchTwins have same teacher at 9 (from admin database), 1Y 0Nadminitemintegernominal0=no, 1=yes
it2ac1/22-subject (English, Maths) mean NC level (9 year teacher), 1-5 teacherderived decimalscale value1 to 5 (NC level)
it3ac1/23-subject (English, maths, science) mean NC level (9 year teacher), 1-5teacherderiveddecimal scale value1 to 5 (NC level)
itage1/2Age of twin (years) when teacher booklet returned at 9 adminderiveddecimalquantitativeapprox. 8.4 to 10 (years)
itanx061/2Behaviour: insists on doing things over (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps011/2Behaviour: blames others for mistakes (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps021/2Behaviour: illegal activities (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps031/2Behaviour: concerned about school progress (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps03r1/2Reversed version of itaps03, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itaps041/2Behaviour: acts without thinking (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps051/2Behaviour: shallow emotions (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps061/2Behaviour: lies easily (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps071/2Behaviour: keeps promises (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps07r1/2Reversed version of itaps07, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itaps081/2Behaviour: brags excessively (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps091/2Behaviour: easily bored (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps101/2Behaviour: uses other people (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps111/2Behaviour: teases or makes fun (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps121/2Behaviour: feels guilty (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps12r1/2Reversed version of itaps12, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itaps131/2Behaviour: risky activities (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps141/2Behaviour: insincerely charming (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps151/2Behaviour: angry when corrected (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps161/2Behaviour: thinks more important (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps171/2Behaviour: does not plan ahead (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps181/2Behaviour: concerned about feelings (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps18r1/2Reversed version of itaps18, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itaps191/2Behaviour: does not show feelings (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps201/2Behaviour: keeps same friends (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itaps20r1/2Reversed version of itaps20, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itapscalt1/2APSD Callous-Unemotional scale (teacher), 0-12 parentderiveddecimalscale value0 to 12
itapsdt1/2APSD overall total scale (teacher), 0-40parent deriveddecimalscale value0 to 40
itapsecalt1/2APSD Enhanced Callous-Unemotional scale (teacher), 0-16parentderiveddecimalscale value0 to 16
itapsimpt1/2APSD Impulsivity scale (teacher), 0-10 parentderiveddecimalscale value0 to 10
itapsnart1/2APSD Narcissism scale (teacher), 0-14 parentderiveddecimalscale value0 to 14
itcas011/2Behaviour: wants to fit in with peers (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas01r1/2Reversed version of itcas01, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itcas021/2Behaviour: odd communication style (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas031/2Behaviour: interest in unusual topic (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas041/2Behaviour: one-sided social behaviour (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas051/2Behaviour: can keep conversation going (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas05r1/2Reversed version of itcas051, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itcas061/2Behaviour: same interests as peers (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas06r1/2Reversed version of itcas06, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itcas071/2Behaviour: unusual movements (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas081/2Behaviour: unusual memory for detail (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas091/2Behaviour: tactless (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas101/2Behaviour: turns conversations (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas111/2Behaviour: loses the listener (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas131/2Behaviour: likes to do things over (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas141/2Behaviour: prefers imaginative activities (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas161/2Behaviour: unusual eye gaze (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas171/2Behaviour: interacts easily with children (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas17r1/2Reversed version of itcas17, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itcas181/2Behaviour: people are important (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas18r1/2Reversed version of itcas18, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itcas191/2Behaviour: cares how perceived by class (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcas19r1/2Reversed version of itcas19, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itcas201/2Behaviour: takes things literally (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcascomt1/2CAST Communication scale at 9 (teacher), 0-14 teacherderiveddecimalscale value0 to 14
itcasnont1/2CAST Non-Social scale at 9 (teacher), 0-10 teacherderiveddecimalscale value0 to 10
itcassoct1/2CAST Social scale at 9 (teacher), 0-14 teacherderiveddecimalscale value0 to 14
itcastt1/2CAST overall total at 9 (teacher), 0-38 teacherderiveddecimalscale value0 to 38
itcla11/2Classroom: likes to be (teacher at 9), see value labelsteacheritemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
itcla21/2Classroom: friends care about work (teacher at 9), see value labelsteacheritemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
itcla31/2Classroom: has fun (teacher at 9), see value labels teacheritemintegerordinal0=not true, 1=somewhat true, 2=certainly true
itcla41/2Classroom: friends try their best (teacher at 9), see value labelsteacheritemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
itcla51/2Classroom: friends enjoy learning (teacher at 9), see value labelsteacheritemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
itcla61/2Classroom: feels happy (teacher at 9), see value labelsteacheritemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
itcla71/2Classroom: feels proud (teacher at 9), see value labelsteacheritemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
itcla81/2Classroom: friends get in trouble (teacher at 9), see value labelsteacheritemintegerordinal 0=not true, 1=somewhat true, 2=certainly true
itclasz1/2Class size at 9, see value labelsteacher itemintegerordinal1=less than 20, 2=20-30, 3=more than 30
itcoga11/2Behaviour: is clever (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcoga21/2Behaviour: solves problems (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcoga31/2Behaviour: finds learning easy (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itcom011/2Communication: people can understand (teacher at 9), see value labelsteacheriteminteger nominal0=not true, 1=somewhat true, 2=certainly true
itcom021/2Communication: rarely makes mistakes (teacher at 9), see value labelsteacheriteminteger nominal0=not true, 1=somewhat true, 2=certainly true
itcom031/2Communication: speech sounds like younger (teacher at 9), see value labelsteacheriteminteger nominal0=not true, 1=somewhat true, 2=certainly true
itcom041/2Communication: sentences harder to understand (teacher at 9), see value labelsteacheritem integernominal0=not true, 1=somewhat true, 2=certainly true, 3=don't know
itcom051/2Communication: speech is 2 or 3 word phrases (teacher at 9), see value labelsteacheriteminteger nominal0=not true, 1=somewhat true, 2=certainly true
itcom061/2Communication: can say long sentences (teacher at 9), see value labelsteacheriteminteger nominal0=not true, 1=somewhat true, 2=certainly true
itcom071/2Communication: leaves out words and endings (teacher at 9), see value labelsteacheriteminteger nominal0=not true, 1=somewhat true, 2=certainly true
itcom081/2Communication: makes mistakes on pronouns (teacher at 9), see value labelsteacheriteminteger nominal0=not true, 1=somewhat true, 2=certainly true
itcom091/2Communication: can give easy-to-follow account (teacher at 9), see value labelsteacheritem integernominal0=not true, 1=somewhat true, 2=certainly true, 3=don't know
itcom101/2Communication: can talk clearly about future (teacher at 9), see value labelsteacheriteminteger nominal0=not true, 1=somewhat true, 2=certainly true
itcom111/2Communication: finds it hard to tell story (teacher at 9), see value labelsteacheriteminteger nominal0=not true, 1=somewhat true, 2=certainly true
itcom121/2Communication: uses words like he or it (teacher at 9), see value labelsteacheriteminteger nominal0=not true, 1=somewhat true, 2=certainly true
itcpeer1/2CEQ Friends/Peer Context (teacher) mean scale at 9, 0-2teacherderiveddecimalscale value 0 to 2
itcsati1/2CEQ Classroom Satisfaction (teacher) mean scale at 9, 0-2teacherderiveddecimalscale value 0 to 2
itdata1/2Teacher booklet data present at 9, 1Y 0N teacheritemintegernominal0=no, 1=yes
itemi11/2Behaviour: makes most of tedious tasks (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itemi21/2Behaviour: likes using brain (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itemi31/2Behaviour: takes criticism (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itemi41/2Behaviour: puts in more effort to improve (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itemi51/2Behaviour: fun more important than work (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
iteng1/2English mean NC level (9 year teacher), 1-5teacherderiveddecimalscale value1 to 5 (NC level)
itengre1/2English Reading (teacher NC rating at 9), 1-5 teacheritemintegerquantitative1 to 5
itengsp1/2English Speaking and Listening (teacher NC rating at 9), 1-5teacheritemintegerquantitative 1 to 5
itengwr1/2English Writing (teacher NC rating at 9), 1-5 teacheritemintegerquantitative1 to 5
itgoo011/2Good at reading (teacher at 9), see value labels teacheritemintegerordinal1=excellent, 2=very good, 3=satisfactory, 4=poor, 5=very poor
itgoo021/2Good at writing (teacher at 9), see value labels teacheritemintegerordinal1=excellent, 2=very good, 3=satisfactory, 4=poor, 5=very poor
itgoo031/2Good at spelling (teacher at 9), see value labels teacheritemintegerordinal1=excellent, 2=very good, 3=satisfactory, 4=poor, 5=very poor
itgoo041/2Good at solving number problems (teacher at 9), see value labelsteacheritemintegerordinal 1=excellent, 2=very good, 3=satisfactory, 4=poor, 5=very poor
itgoo051/2Good at mental arithmetic (teacher at 9), see value labelsteacheritemintegerordinal 1=excellent, 2=very good, 3=satisfactory, 4=poor, 5=very poor
itgoo061/2Good at multiplying and dividing (teacher at 9), see value labelsteacheritemintegerordinal 1=excellent, 2=very good, 3=satisfactory, 4=poor, 5=very poor
itgoo071/2Good at learning about nature (teacher at 9), see value labelsteacheritemintegerordinal 1=excellent, 2=very good, 3=satisfactory, 4=poor, 5=very poor
itgoo081/2Good at testing things out (teacher at 9), see value labelsteacheritemintegerordinal 1=excellent, 2=very good, 3=satisfactory, 4=poor, 5=very poor
itgoo091/2Good at finding out how things work (teacher at 9), see value labelsteacheriteminteger ordinal1=excellent, 2=very good, 3=satisfactory, 4=poor, 5=very poor
itgoo101/2Good at team games (teacher at 9), see value labels teacheritemintegerordinal1=excellent, 2=very good, 3=satisfactory, 4=poor, 5=very poor
itgoo111/2Good at races and competitions (teacher at 9), see value labelsteacheritemintegerordinal 1=excellent, 2=very good, 3=satisfactory, 4=poor, 5=very poor
itgoo121/2Good at PE classes (teacher at 9), see value labels teacheritemintegerordinal1=excellent, 2=very good, 3=satisfactory, 4=poor, 5=very poor
ithwfin1/2Homework: usually finishes (teacher at 9), see value labelsteacheritemintegerordinal 0=none, 1=little, 2=some of it, 3=most of it, 4=all of it
ithwinv1/2Homework: involves others (teacher at 9), 1Y 0N teacheritemintegernominal0=no, 1=yes
ithwnts1/2Homework: nights per week (teacher at 9), 0-5 teacheritemintegerquantitative0 to 5
itliaca1/2Academic Liking scale, Teacher-rated at 9 (1-5) teacherderiveddecimalscale value1 to 5
itlieng1/2English Liking scale, Teacher-rated at 9 (1-5) teacherderiveddecimalscale value1 to 5
itlik011/2Likes reading (teacher at 9), see value labels teacheritemintegerordinal1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
itlik021/2Likes writing (teacher at 9), see value labels teacheritemintegerordinal1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
itlik031/2Likes spelling (teacher at 9), see value labels teacheritemintegerordinal1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
itlik041/2Likes solving number problems (teacher at 9), see value labelsteacheritemintegerordinal 1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
itlik051/2Likes mental arithmetic (teacher at 9), see value labelsteacheritemintegerordinal 1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
itlik061/2Likes multiplying and dividing (teacher at 9), see value labelsteacheritemintegerordinal 1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
itlik071/2Likes learning about nature (teacher at 9), see value labelsteacheritemintegerordinal 1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
itlik081/2Likes testing things out (teacher at 9), see value labelsteacheritemintegerordinal 1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
itlik091/2Likes finding out how things work (teacher at 9), see value labelsteacheritemintegerordinal 1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
itlik101/2Likes team games (teacher at 9), see value labels teacheritemintegerordinal1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
itlik111/2Likes races and competitions (teacher at 9), see value labelsteacheritemintegerordinal 1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
itlik121/2Likes PE classes (teacher at 9), see value labels teacheritemintegerordinal1=like it very much, 2=do like it, 3=it's OK, 4=don't like it, 5=don't like at all
itlimat1/2Maths Liking scale, Teacher-rated at 9 (1-5) teacherderiveddecimalscale value1 to 5
itliphy1/2Physical Education Liking scale, Teacher-rated at 9 (1-5)teacherderiveddecimalscale value 1 to 5
itlisci1/2Science Liking scale, Teacher-rated at 9 (1-5) teacherderiveddecimalscale value1 to 5
itLLCage1Age of twin when 9yr teacher booklet returned (for use in LLC TRE), months teacherderivedintegerquantitative approx. 102 to 118 (months)
itLLCdate1Date when 9yr teacher booklet returned (for use in LLC TRE), yyyy-mm string teacherderivedstringdate value approx. '2003-04' to '2004-08'
itmat1/2Maths mean NC level (9 year teacher), 1-5teacherderiveddecimalscale value1 to 5 (NC level)
itmatnu1/2Maths Number and Algebra (teacher NC rating at 9), 1-5teacheritemintegerquantitative 1 to 5
itmatsh1/2Maths Shape Space and Measures (teacher NC rating at 9), 1-5teacheritemintegerquantitative 1 to 5
itmatus1/2Maths Using and Applying (teacher NC rating at 9), 1-5teacheritemintegerquantitative 1 to 5
itmoaca1/2Academic Overall Motivational scale, Teacher-rated at 9 (1-5)teacherderiveddecimalscale value 1 to 5
itodd11/2Behaviour: argues with adults (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itodd31/2Behaviour: deliberately annoys (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itodd41/2Behaviour: touchy (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itodd51/2Behaviour: often angry (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itodd61/2Behaviour: spiteful (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itoddt1/2ODD total scale (teacher at 9), 0-10teacherderiveddecimalscale0 to 10
itpaaca1/2Academic Perceived Ability scale, Teacher-rated at 9 (1-5)teacherderiveddecimalscale value 1 to 5
itpaeng1/2English Perceived Ability scale, Teacher-rated at 9 (1-5)teacherderiveddecimalscale value 1 to 5
itpag11/2Behaviour: uses physical force (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itpag21/2Behaviour: threatens and bullies (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itpag31/2Behaviour: gets others to gang up (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itpagt1/2Proactive Aggression scale (teacher), 0-6 parentderiveddecimalscale value0 to 6
itpamat1/2Maths Perceived Ability scale, Teacher-rated at 9 (1-5)teacherderiveddecimalscale value 1 to 5
itpaphy1/2Physical Education Perceived Ability scale, Teacher-rated at 9 (1-5)teacherderiveddecimal scale value1 to 5
itpasci1/2Science Perceived Ability scale, Teacher-rated at 9 (1-5)teacherderiveddecimalscale value 1 to 5
itrag11/2Behaviour: blames others in fights (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itrag21/2Behaviour: strikes back when teased (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itrag31/2Behaviour: overreacts angrily (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itragt1/2Reactive Aggression scale (teacher), 0-6 parentderiveddecimalscale value0 to 6
itsci1/2Science mean NC level (9 year teacher), 1-5teacherderiveddecimalscale value1 to 5 (NC level)
itschtp1/2School type at 9, 1state 2privateteacher itemintegernominal1=state, 2=private
itscili1/2Science Life Processes (teacher NC rating at 9), 1-5 teacheritemintegerquantitative1 to 5
itsciph1/2Science Physical Processes (teacher NC rating at 9), 1-5teacheritemintegerquantitative 1 to 5
itscisc1/2Science Scientific Enquiry (teacher NC rating at 9), 1-5teacheritemintegerquantitative 1 to 5
itsdqbeht1/2SDQ Behaviour Problems total (teacher) at 9, 0-40 teacherderiveddecimalscale value0 to 40
itsdqcon11/2Behaviour: temper tantrums (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqcon21/2Behaviour: obedient (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqcon2r1/2Reversed version of itsdqcon2, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itsdqcon31/2Behaviour: often fights (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqcon41/2Behaviour: often lies or cheats (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqcon51/2Behaviour: steals (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqcont1/2SDQ Conduct scale (teacher) at 9, 0-10 teacherderiveddecimalscale value0 to 10
itsdqemo11/2Behaviour: complains of headaches (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqemo21/2Behaviour: many worries (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqemo31/2Behaviour: often unhappy (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqemo41/2Behaviour: nervous in new situations (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqemo51/2Behaviour: many fears (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqemot1/2SDQ Emotion scale (teacher) at 9, 0-10 teacherderiveddecimalscale value0 to 10
itsdqhyp11/2Behaviour: restless or overactive (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqhyp21/2Behaviour: fidgets or squirms (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqhyp31/2Behaviour: easily distracted (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqhyp41/2Behaviour: thinks things out (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqhyp4r1/2Reversed version of itsdqhyp4, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itsdqhyp51/2Behaviour: sees tasks through (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqhyp5r1/2Reversed version of itsdqhyp5, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itsdqhypt1/2SDQ Hyperactivity scale (teacher) at 9, 0-10 teacherderiveddecimalscale value0 to 10
itsdqper11/2Behaviour: solitary (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqper21/2Behaviour: has at least one good friend (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqper2r1/2Reversed version of itsdqper2, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itsdqper31/2Behaviour: generally liked (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqper3r1/2Reversed version of itsdqper31, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itsdqper41/2Behaviour: picked on or bullied (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqper51/2Behaviour: gets on better with adults (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqpert1/2SDQ Peer Problem scale (teacher) at 9, 0-10 teacherderiveddecimalscale value0 to 10
itsdqpro11/2Behaviour: considerate (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqpro21/2Behaviour: shares readily (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqpro31/2Behaviour: helpful if someone hurt (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqpro3r1/2Reversed version of itsdqpro3, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itsdqpro41/2Behaviour: kind to younger children (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqpro4r1/2Reversed version of itsdqpro4, see value labelsteacheritemintegerordinal0=very true, 1=quite true, 2=not true
itsdqpro51/2Behaviour: often volunteers to help (teacher at 9), see value labelsteacheritemintegerordinal0=not true, 1=quite true, 2=very true
itsdqprot1/2SDQ Prosocial scale (teacher) at 9, 0-10 teacherderiveddecimalscale value0 to 10
itsen1/2Has a Statement of SEN (teacher at 9), 1Y 0N teacheritemintegernominal0=no, 1=yes
itsenrg1/2On the SEN Register (teacher at 9), 1Y 0N teacheritemintegernominal0=no, 1=yes