Table 1

Characteristics of children and young people with and without ADHD

CharacteristicCases
n=8127
Controls
n=40 136
Sex, n (%)
 Male6716 (82.6)33 164 (82.6)
Age group at diagnosis (years), n (%)
 4176 (2.2)1013 (2.5)
 5–61445 (17.8)7092 (17.7)
 7–103661 (45.1)17 943 (44.7)
 11–172845 (35.0)14 088 (35.1)
Period of start of study, n (%)
 1998–19992137 (26.3)11 185 (27.9)
 2000–20043548 (43.6)17 373 (43.3)
 2005–20092062 (25.4)9965 (24.8)
 2010–2015380 (4.7)1613 (4.0)
Deprivation quintile, n (%)
 1st quintile (least deprived)1355 (16.7)8879 (22.1)
 2nd quintile1366 (16.8)7818 (19.5)
 3rd quintile1527 (18.8)7769 (19.4)
 4th quintile1751 (21.6)7602 (18.9)
 5th quintile (most deprived)2120 (26.1)8020 (20.0)
 Data missing8 (0.1)48 (0.1)
Region, n (%)
 North East193 (2.4)958 (2.4)
 North West1118 (13.8)5517 (13.8)
 Yorkshire & The Humber164 (2.0)813 (2.0)
 East Midlands263 (3.2)1289 (3.2)
 West Midlands763 (9.4)3757 (9.4)
 East of England1180 (14.5)5789 (14.4)
 South West787 (9.7)3887 (9.7)
 South Central1206 (14.8)5974 (14.9)
 London871 (10.7)4297 (10.7)
 South East Coast1582 (19.5)7855 (19.6)
  • Sex, age and practice were matching variables. Therefore, cases and controls were registered at the same GP practice.

  • ADHD, attention-deficit/hyperactivity disorder ; GP, general practitioner.