Attributed causes of wheezing in the three surveys
| Causative factor | 1973 | 1988 | 2003 | Difference 2003–1988(95% CI) % | |||
|---|---|---|---|---|---|---|---|
| N | % of all wheezers(n = 138) | N | % of all wheezers(n = 215) | N | % of all wheezers(n = 321) | ||
| Colds | 125 | 90.6 | 166 | 77.2 | 267 | 83.2 | 6.0 (−0.8 to 13.1) |
| Running | 47 | 34.1 | 101 | 47.0 | 184 | 57.3 | 10.3 (1.7 to 18.8) |
| Worry | 22 | 15.9 | 27 | 12.6 | 44 | 13.7 | 1.1 (−4.9 to 6.8) |
| Excitement | 27 | 19.6 | 44 | 20.5 | 43 | 13.4 | −7.1 (−13.8 to −0.7) |
| Animals | 14 | 10.1 | 35 | 16.3 | 65 | 20.2 | 4.0 (−2.9 to 10.4) |
| Food | 1 | 0.7 | 16 | 7.4 | 10 | 3.1 | −4.3 (−8.9 to −0.6) |