Table 1.
Sample characteristics.
| Variable | SCZ | BD | MDD | ADHD | ASD | AN | Controls |
|---|---|---|---|---|---|---|---|
| Sample size | 1356 | 839 | 9719 | 5238 | 3859 | 1680 | 12,487 |
| Females | 668 (49.3%) | 561 (66.9%) | 6836 (70.3%) | 1748 (33.4%) | 1017 (26.4%) | 1568 (93.3%) | 6327 (50.7%) |
| Age on Dec 2016 | 26.1 (2.9) | 26.8 (2.8) | 26.2 (3.3) | 22.9 (4.1) | 22.1 (3.9) | 24.8 (3.7) | 23.4 (4.2) |
| Exam agea | 15.7 (0.4) | 15.6 (0.4) | 15.6 (0.4) | 15.8 (0.4) | 15.8 (0.5) | 15.6 (0.4) | 15.6 (0.4) |
| Age at first diagnosisb | 21.15 (2.9) | 21.86 (3.2) | 18.9 (3.3) | 14.8 (5.6) | 12.8 (5.0) | 16.3 (3.3) | – |
| Diagnosed before examc | 38 (2.8%) | 17 (2.1%) | 1655 (17.1%) | 3025 (57.8%) | 2880 (74.6%) | 819 (48.9%) | – |
| Mean school gradesd | 6.0 (2.2) | 6.8 (2.3) | 6.4 (2.3) | 5.3 (2.2) | 6.7 (2.3) | 8.0 (2.3) | 6.9 (2.4) |
The values represent either frequency (proportion) if categorical variable or mean (SD) if continuous variable.
aExam age is the age of the individuals when they sat for the exit exam.
bThe age at first diagnosis was calculated based on the first time the diagnosis was recorded in the register.
cThe date of first diagnosis and the date of exit exam were compared to identify if the individual has received the diagnosis before they sat for the exam.
dThe mean value was calculated across all the grades: Danish written, oral and grammar and English oral and mathematics written and oral (if sat for the exam before on or before 2006) or problem solving (if sat for the exam after 2006); The lowest and highest mean values observed were − 1.7 and 12.