Table 1 Characteristics of the study participants.
From: Gender dysphoria in twins: a register-based population study
Concordant twins (N = 10, not unique) | Discordant twins (N = 57) | Concordant non-twin sibling pairs (N = 4, not unique) | Discordant non-twin sibling pairs (N = 2530) | |
|---|---|---|---|---|
Age at first diagnosis, years | ||||
Mean age of proband at first diagnosis (SD) | 32.1 (14.8) | 25.5 (10.8) | 24.7 (4.7) | 27.4 (11.6) |
Mean age difference of first diagnosis between siblings | 3.7 | NA | 6.9 | NA |
p-value (derived from Mann–Whitney U test) | 1.0 | 1.0 | ||
Probands in twin pairs (N = 67) | Siblings in twin pairs (N = 67) | Probands in non-twin pairs (N = 2534) | Siblings in non-twin pairs (N = 2534) | |
|---|---|---|---|---|
Education, N (%) | ||||
9 years or less | 14 (21%) | 11 (16%) | 662 (25%) | 421 (16%) |
10–12 years | 30 (45%) | 33 (49%) | 998 (38%) | 1086 (42%) |
13 years or more | 19 (28%) | 17 (25%) | 837 (32%) | 819 (31%) |
Unknown | 4 (6%) | 6 (9%) | 104 (4%) | 275 (11%) |
Country of birth, N (%) | ||||
Sweden | 59 (88%) | 65 (97%) | 2089 (82%) | 2412 (95%) |
Other Nordic countries | 0 (0%) | 0 (0%) | 16 (1%) | 28 (1%) |
Outside the Nordic countries | 2 (3%) | 2 (3%) | 102 (4%) | 92 (4%) |
Unknown | 6 (9%) | 0 (0%) | 327 (13%) | 2 (0%) |
