| All subjects | Current treatment for asthma | Social class | |||
| No(n = 916) | Yes(n = 143) | I/II(n = 563) | IIIN–V or unclassified(n = 459) | ||
| Age at recruitment (years) | |||||
| 6 | 310 (27.6) | 256 (28.0) | 42 (29.4) | 157 (27.9) | 128 (27.9) |
| 7 | 413 (36.7) | 343 (37.5) | 53 (37.1) | 204 (36.2) | 177 (38.6) |
| 8 | 301 (26.8) | 236 (25.8) | 36 (25.2) | 147 (26.1) | 117 (25.5) |
| 9 | 100 (8.9) | 80 (8.7) | 12 (8.4) | 54 (9.6) | 37 (8.1) |
| 10 | 1 (0.1) | 1 (0.1) | 0 | 1 (0.2) | 0 |
| Sex (female) | 587 (52.2) | 498 (54.4) | 57 (39.9) | 300 (53.3) | 229 (49.9) |
| Asthma | 203 (18.4) | 74 (8.2) | 119 (85.6) | 99 (17.9) | 93 (20.6) |
| Current wheeze | 184 (16.4) | 62 (6.8) | 120 (83.9) | 86 (15.3) | 82 (18.0) |
| Maternal asthma | 155 (14.3) | 101 (11.4) | 45 (32.9) | 76 (13.9) | 68 (15.4) |
| Paternal asthma | 128 (12.2) | 100 (11.7) | 24 (18.6) | 64 (11.8) | 57 (13.5) |
| First born | 461 (41.1) | 376 (41.1) | 58 (41.1) | 266 (47.3) | 153 (33.4) |
| Non-white ethnicity | 376 (33.8) | 295 (32.4) | 57 (40.7) | 115 (20.6) | 205 (45.2) |
| Parental smoking in the home | 356 (31.9) | 293 (32.3) | 41 (28.7) | 88 (15.9) | 225 (49.1) |
| Mould in the home | 198 (18.1) | 157 (17.7) | 29 (20.7) | 81 (14.7) | 100 (22.6) |
| Gas cooker in the home | 825 (74.0) | 673 (74.3) | 105 (73.4) | 420 (75.5) | 330 (72.4) |
| Ownership of furry pets | 460 (42.3) | 387 (43.4) | 48 (34.8) | 272 (50.0) | 162 (36.5) |
Data shown as n (%).