Table 1.
Descriptive characteristics for the singleton and twin study population (by 31 December 1995).
| Singletons | Twins | |
|---|---|---|
| Total, n | 52,388 | 15,261 |
| Complete twin pairs/single twins | – | 4220/6821 |
| Age 46–50, n (%) | 9836 (18.8) | 3773 (24.7) |
| Years of education, median (IQR) | 13 (8–13) | 12 (7–13) |
| Deathsa, n (%) | 1780 (18.1) | 714 (18.9) |
| Age 51–55, n (%) | 8320 (15.9) | 3097 (20.3) |
| Years of education, median (IQR) | 11 (7–13) | 10 (7–13) |
| Deathsa, n (%) | 2262 (27.2) | 882 (28.5) |
| Age 56–60, n (%) | 6688 (12.8) | 2345 (15.4) |
| Years of education, median (IQR) | 9 (7–13) | 7 (7–13) |
| Deathsa, n (%) | 2887 (43.2) | 990 (42.2) |
| Age 61–65, n (%) | 5885 (11.2) | 1920 (12.6) |
| Years of education, median (IQR) | 7 (7–13) | 7 (7–13) |
| Deathsa, n (%) | 3761 (63.9) | 1272 (66.3) |
| Age 66–70, n (%) | 5831 (11.1) | 1133 (7.4) |
| Years of education, median (IQR) | 7 (7–13) | 7 (7–12) |
| Deathsa, n (%) | 4830 (82.8) | 962 (84.9) |
| Age 71–75, n (%) | 5659 (10.8) | 1068 (7.0) |
| Years of education, median (IQR) | 7 (7–12) | 7 (7–11) |
| Deathsa, n (%) | 5396 (95.4) | 1030 (96.4) |
| Age 76–80, n (%) | 4254 (8.1) | 817 (5.4) |
| Years of education, median (IQR) | – | – |
| Deathsa, n (%) | 4232 (99.5) | 817 (100) |
| Age 81 + , n (%) | 5915 (11.3) | 1108 (7.3) |
| Years of education, median (IQR) | – | – |
| Deathsa, n (%) | 5910 (99.9) | 1108 (100) |
IQR, interquartile range.
aNumber of deaths from 31st of December 1995 until end of follow-up (31st of December 2020). Percentages are calculated for each age group.