Estimated risk of childhood prescription of medications for attention-deficit/hyperactivity disorder among children born to birth parents admitted for delivery between 31 + 0 and 33 + 6 weeks’ gestation versus those admitted between 34 + 0 and 36 + 6 weeks’ gestation in British Columbia, Canada, 2000–2013
| Prescription | Rate ratio (95% CI) | Excess cases per 100 children by 13 years of age* (95% CI) |
|---|---|---|
| ≥ 1 dispensation | 1.12 (0.8 to 1.6) | 1.3 (−2.5 to 5.7) |
| ≥ 2 dispensations | 1.1 (0.7 to 1.7) | 1.3 (−3.1 to 5.6) |
Note: CI = confidence interval.
↵* Absolute difference in cumulative risk by age 13.