Characteristics of the study population, The Finnish Environment and Asthma Study 1997–2000
| Characteristics | Cases | Controls |
| Total n | 521 | 932 |
| Sex | ||
| Male | 175 (33.6) | 438 (47.0) |
| Female | 346 (66.4) | 494 (53.0) |
| Age yrs | ||
| 21–29 | 108 (20.7) | 141 (15.1) |
| 30–39 | 107 (20.5) | 224 (24.0) |
| 40–49 | 125 (24.0) | 254 (27.3) |
| 50–59 | 140 (26.9) | 240 (25.8) |
| 60–63 | 41 (7.9) | 73 (7.8) |
| Parental allergic diseases | ||
| Maternal allergy | 85 (16.3) | 108 (11.6) |
| Paternal allergy | 47 (9.0) | 48 (5.2) |
| Maternal asthma | 66 (12.7) | 64 (6.9) |
| Paternal asthma | 62 (11.9) | 48 (5.2) |
| Any | 186 (35.7) | 204 (21.9) |
| Education# | ||
| No vocational schooling | 107 (20.6) | 154 (16.6) |
| Vocational course | 89 (17.2) | 104 (11.2) |
| Vocational institution | 149 (28.7) | 271 (29.2) |
| College-level education | 113 (21.8) | 261 (28.1) |
| University or corresponding | 61 (11.8) | 138 (14.9) |
| ETS | ||
| At work | 89 (17.1) | 130 (13.9) |
| At home | 30 (5.9) | 52 (5.6) |
| Pets at home | ||
| Never | 134 (25.7) | 269 (28.9) |
| Currently | 222 (42.7) | 420 (45.1) |
| >12 months ago | 165 (31.7) | 243 (26.1) |
| Sometimes | 387 (74.3) | 663 (71.1) |
| Indoor mould exposure at work or at home | 123 (23.8) | 192 (20.7) |
| Any work exposure¶ | 313 (60.1) | 579 (62.1) |
Data are presented as n and n (%)
ETS: environmental tobacco smoke
#: data missing for six subjects
¶: self-reported exposure to sensitisers, dusts and/or fumes