TEDS Data Dictionary

21 Year Data Returns

Contents of this page:

Introduction

This page summarises returns in the various parts of the 21 year study: TEDS 21 phase 1 (parent and twins), TEDS 21 phase 2 (twins only), the G-game and all phases of the Covid twin study. These data collections were administered largely independently from each other, and at different times, hence the data returns involve sets of twins/families that are not entirely overlapping.

The figures in the table below are based on information logged in the TEDS admin database. For the TEDS 21 study, the figures include all methods of data collection: paper booklets, app (used on mobile devices) and web (used on desktops and laptops). For the G-game and Covid studies, all data were collected via the web.

The main 21 Year Study page gives full details of how the data were collected.

Returns

The figures shown in the table below are numbers of families (twin pairs).

For the sake of simplicity, where data were collected on line, "completed" means that the online activities were finished - the numbers do not include cases where the online activities were started but not finished (data present but incomplete).

Original ONS sample 16810
TEDS 21 Phase 1 parent study Parents contacted 10451
Completed 5352
Percentage completed 51.2%
TEDS 21 Phase 1 twin study Twin pairs contacted 10535
Completed by both twins 4128
Completed by one twin 1443
Percentage completed: both twins 39.2%
Percentage completed: one twin only 13.7%
TEDS 21 Phase 2 twin study Twin pairs contacted 8611
Completed by both twins 3536
Completed by one twin 1648
Percentage completed: both twins 41.1%
Percentage completed: one twin only 19.1%
TEDS 21 Phase 1 combined
(parents and twins)
Families contacted 10577
Completed by parent and both twins 3664
Completed by parent and one twin 694
Completed by both twins but not parent 464
Completed by parent but neither twin 994
Completed by one twin only 749
TEDS 21 Phases 1 and 2 combined
(twins, ignoring parents)
Twin pairs contacted in both phases 8535
Completed by both twins in both phases 3352
Percentage completed by both twins, both phases 39.3%
Phase 1 completed by both twins (phase 2 incomplete) 776
Phase 2 completed by both twins (phase 1 incomplete) 184
Completed by one twin only, either or both phases 1525
G-game twin study Twin pairs in which both twins contacted 6685
Twin pairs in which only one twin contacted 1261
Total individual twins contacted 14631
Completed by both twins 1491
Percentage of twin pairs completed 22.3%
Completed by one twin 1769
Total individual twins completed 4751
Percentage of individual twins completed 32.5%
Covid Phase 1 twin study Twin pairs in which both twins contacted 6673
Twin pairs in which only one twin contacted 1272
Total individual twins contacted 14618
Completed by both twins 1494
Percentage of twin pairs completed 22.4%
Completed by one twin 1931
Total individual twins completed 4919
Percentage of individual twins completed 33.7%
Covid Phase 2 twin study Twin pairs in which both twins contacted 4061
Twin pairs in which only one twin contacted 277
Total individual twins contacted 8399
Completed by both twins 1228
Percentage of twin pairs completed 30.2%
Completed by one twin 1608
Total individual twins completed 4064
Percentage of individual twins completed 48.4%
Covid Phase 3 twin study Twin pairs in which both twins contacted 4068
Twin pairs in which only one twin contacted 275
Total individual twins contacted 8411
Completed by both twins 1100
Percentage of twin pairs completed 27.0%
Completed by one twin 1471
Total individual twins completed 3671
Percentage of individual twins completed 43.6%
Covid Phase 4 twin study Twin pairs in which both twins contacted 4059
Twin pairs in which only one twin contacted 284
Total individual twins contacted 8402
Completed by both twins 1150
Percentage of twin pairs completed 28.3%
Completed by one twin 1596
Total individual twins completed 3896
Percentage of individual twins completed 46.4%
Covid study across phases Both twins invited in all 4 phases 4026
Completed by both twins in all 4 phases 495
Completed by both twins across 2 or 3 phases 893
Completed by both twins in 1 phase only 791