Characteristics of the study participants
| Participant characteristics | n (N; %) |
|---|---|
| N, total number of participants. | |
| *Was mother working in 1968? | |
| †History of pneumonia, diphtheria or pertussis. | |
| ‡History of measles, mumps, rubella or chicken pox. | |
| Sex | |
| Female | 4014 (8215; 49) |
| Birthplace | |
| Tasmania | 7396 (8179; 90.4) |
| Other states in Australia | 480 (8179; 5.9) |
| UK, US, NZ, Canada, or South Africa | 237 (8179; 3.0) |
| Other | 66 (8179; 0.1) |
| Feeding in the first 3 months | |
| Bottle-fed only | 2327 (8142; 28.6) |
| Bottle-fed + breast-fed | 2620 (8142; 32.2) |
| Breast-fed only | 3195 (8142; 39.2) |
| Parental smoking in 1968 | |
| Neither parents smoke | 2291 (7291; 31.4) |
| Father smokes | 2404 (7291; 33.0) |
| Mother smokes | 593 (7291; 8.1) |
| Both mother and father smoke | 2003 (7291; 27.5) |
| Parental asthma in 1968 | |
| Neither parents have/had asthma | 5929 (7395; 80.2) |
| Father has/had asthma | 661 (7395; 8.9) |
| Mother has/had asthma | 674 (7395; 9.1) |
| Both parents have/had asthma | 131 (7395; 1.8) |
| Mother employed in 1968* | 1699 (7634; 22.2) |
| First-born child | 2330 (8054; 28.9) |
| Any past bacterial infection† | 1428 (8167; 17.5) |
| Any past viral infection‡ | 6570 (8169; 80.0) |
| Any history of pneumonia | 812 (8179; 9.9) |
| Any history of pertussis | 719 (8173; 9.0) |
| Had asthma by age 7 years | 1319 (8215; 16.1) |
| Had asthma by age 13 years | 1717 (7436; 23.1) |
| Had eczema by age 7 years | 783 (8126; 9.6) |
| Had food allergy by age 7 years | 564 (8158; 6.9) |
| Had hay fever by age 7 years | 1032 (8193; 12.6) |