Table 2.
Deprivation adjusted incidence rate ratios for neurodevelopmental disorders between first and final year of the study’s observation period by age group
| Aged 1–5 | Aged 6–9 | Aged 10–12 | Aged 13–16 | Aged 17–19 | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 2003 | 2018 | 2003 | 2018 | 2003 | 2018 | 2003 | 2018 | 2003 | 2018 | |
| Female | ||||||||||
| ADHD | ||||||||||
| Cases, n | 28 | 24 | 80 | 252 | 32 | 117 | 20 | 106 | a | 34 |
| Incidence rate | 2 | 1 | 5 | 13 | 3 | 9 | 1 | 6 | 0 | 3 |
| Incidence rate ratio | 0.7 | 2.5 | 3.0 | 4.6 | 14.3 | |||||
| (95% CI) | (0.4, 1.3) | (1.9, 3.2) | (2.0, 4.2) | (2.8, 7.4) | (3.4, 59.7) | |||||
| Autism | ||||||||||
| Cases, n | 90 | 372 | 31 | 302 | 17 | 192 | 12 | 187 | 8 | 43 |
| Incidence rate | 5 | 17 | 2 | 16 | 2 | 14 | 1 | 11 | 1 | 4 |
| Incidence rate ratio | 3.5 | 7.5 | 9.2 | 13.0 | 4.6 | |||||
| (95% CI) | (2.8, 4.5) | (5.1, 11.1) | (5.6, 15.1) | (7.1, 23.9) | (2.2, 9.8) | |||||
| Male | ||||||||||
| ADHD | ||||||||||
| Cases, n | 153 | 110 | 454 | 987 | 233 | 431 | 129 | 351 | 20 | 76 |
| Incidence rate | 8 | 5 | 27 | 50 | 18 | 31 | 8 | 20 | 2 | 6 |
| Incidence rate ratio | 0.6 | 1.9 | 1.7 | 2.6 | 3.5 | |||||
| (95% CI) | (0.5, 0.8) | (1.6, 2.2) | (1.4, 2.0) | (2.1, 3.3) | (2.1, 5.7) | |||||
| Autism | ||||||||||
| Cases, n | 379 | 1334 | 221 | 964 | 99 | 448 | 60 | 315 | 20 | 85 |
| Incidence rate | 20 | 60 | 13 | 50 | 8 | 33 | 4 | 18 | 2 | 7 |
| Incidence rate ratio | 3.2 | 3.8 | 4.5 | 5.1 | 4.0 | |||||
| (95% CI) | (2.7, 3.8) | (3.2, 4.4) | (3.3, 5.3) | (3.7, 7.1) | (2.5, 6.5) | |||||
Incidence rates are per 10,000 person years and were directly standardised for Index of Multiple Deprivation (IMD) quintile. Incidence rates are rounded to closest interger.
a The CPRD stipulates that cell counts below 5 are masked to protect confidentiality