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. Author manuscript; available in PMC: 2021 Jan 1.
Published in final edited form as: Twin Res Hum Genet. 2019 Jul 31;22(6):800–808. doi: 10.1017/thg.2019.35

Table 1.

The current status of the CODATwins database by country.

Country Twin individuals1 Complete twin pairs1 Number of measures2 Number of twin individuals3
N % of females N % of MZ % of OSDZ BMI Smoking status Birth weight Maternal education Own education
Australia4 26435 61 12116 47 22 58586 35578 2354 2179 23403
Belgium5 803 52 379 64 11 803 803 803 747 803
Brazil6 211 76 97 79 12 211 NA NA NA 206
Canada7 2792 59 1387 46 21 7441 NA 1171 NA NA
China8 22531 50 11264 54 20 22531 1006 19738 943 1006
Denmark9 65459 52 27261 27 33 108790 NA NA NA NA
Finland10 40224 51 18735 29 17 110118 79965 10038 7621 36611
Germany11 2833 72 1395 66 10 2941 478 NA NA 1793
G-Bissau12 253 53 108 15 58 1042 NA 253 NA NA
Hungary13 825 66 387 59 13 825 805 259 NA 303
Israel14 995 49 489 23 35 1228 NA 818 745 NA
Italy15 17361 56 8630 44 25 18834 5651 1904 5767 11417
Japan16 9994 52 4932 54 18 52342 1023 9276 4900 431
Mongolia17 164 50 82 43 22 164 NA 138 NA NA
Netherlands18 44169 53 22023 37 31 157287 NA 33779 34338 5873
Norway19 13941 53 5254 46 0 20188 20004 7900 8327 9228
Portugal20 432 51 216 40 26 432 NA NA 430 NA
S-Korea21 4513 55 2248 59 18 5862 2649 779 3203 1346
Spain22 2258 57 1000 35 27 4392 4358 588 NA 2222
Sri Lanka23 2485 56 933 45 27 2485 NA NA NA 2469
Sweden24 74709 51 33768 33 19 185454 73828 5769 5310 29921
Turkey25 584 46 288 37 27 584 584 NA 584 NA
UK26 32545 61 15865 39 24 112198 NA 21262 3495 NA
USA27 123465 43 59778 42 19 175047 45396 31430 70316 77014
Total 489981 51 228635 39 22 1049785 272128 148259 148905 204046

MZ = monozygotic twins; OSDZ = opposite-sex dizygotic twins; BMI = body mass index; NA = not available.

1

Only twins including information on height, weight, age at the time of measurement, sex and zygosity are included

2

Longitudinal measures available for part of twins

3

Only one measure available for each twin

4

Australian Twin Registry, Peri/Postnatal Epigenetic Twins Study (PETS), Queensland Twin Register

5

East Flanders Prospective Twin Survey

6

Brazilian Twin Registry

7

Quebec Newborn Twin Study, University of British Columbia Twin Project

8

Chinese National Twin Cohort Study, Guangzhou Twin Eye Study, Qingdao Twin Registry (Children), Qingdao Twin Registry (Adults)

9

Danish Twin Cohort

10

Finnish Older Twin Cohort, FinnTwin12, FinnTwin16

11

Berlin Twin Register Health (TwiSt), Bielefeld Longitudinal Study of Adult Twins

12

Guinea Bissau Twin Study

13

Hungarian Twin Registry

14

Longitudinal Israeli Study of Twins

15

Italian Twin Registry

16

Japanese Twin Registry, Ochanomizu University Twin Project, Osaka University Aged Twin Registry, West Japan Twins and Higher Order Multiple Births Registry

17

Mongolian Twin Registry

18

Netherlands Twin cohort (children), Netherlands Twin cohort (adults)

19

Norwegian Twin Registry

20

Portugal Twin Cohort, Madeira Twin Family Study

21

Korean Twin-Family Register, South Korea Twin Registry

22

Murcia Twin Registry

23

Sri Lanka Twin Registry

24

Child and Adolescent Twin Study in Sweden (CATSS), TCHAD-Study, Swedish Twin Cohorts, Swedish Young Male Twins Study

25

Turkish Twin Study

26

Gemini Study, Genesis 12–19 study, Twins Early Developmental Study, TwinsUK

27

Boston University Twin Project, California Twin Program, Carolina African American Twin Study of Aging, Colorado Twin Registry, Michigan Twins Study, Mid-Atlantic Twin Registry, Minnesota Twin Family Study, Minnesota Twin Registry, NAS-NRC Twin Cohort, SRI-International, Texas Twin Project, University of Southern California Twin Study, University of Washington Twin Registry, Vietnam Era Twin Registry