Incidence (IR) of treated attention deficit disorder by calendar year for males aged 5–14 years.
| Year | Number of cases | Person-years | IR × 10−3 (95% CI) |
|---|---|---|---|
| 1996 | 82 | 70181 | 1.2 (0.9 to 1.5) |
| 1997 | 97 | 69419 | 1.4 (1.1 to 1.7) |
| 1998 | 89 | 67722 | 1.3 (1.1 to 1.6) |
| 1999 | 103 | 63486 | 1.6 (1.3 to 2.0) |
| 2000a | 72 | 53130 | 1.4 (1.1 to 1.7) |
| 2001a | 14 | 11000 | 1.3 (0.7 to 2.1) |
↵aA number of practices were updated only through 1999.