ECRHS I subjects* | Number responding to ECRHS I, II and III | ||||||||||
Symptom from postal survey | Number of centres | Number of participants | ECRHS I crude prevalence (%) | Subjects | ECRHS I prevalence (%) | Net change ECRHS II-I (%) | Net change ECRHS III-II (%) | Net change ECRHS III-I (%) (95% CI) | p | Heterogeneity I2 (%) | Heterogeneity p |
Wheeze | 29 | 14 734 | 21.5 | 7738 | 21.3 | −1.6 | −0.6 | −2.4 (−3.5 to −1.3) | 0.000015 | 0.0 | 0.71 |
Wheeze with breathlessness | 29 | 14 699 | 10.9 | 7630 | 10.1 | −0.2 | 0.5 | 0.6 (−0.2 to 1.5) | 0.12 | 0.0 | 0.61 |
Wheeze without a cold | 29 | 14 720 | 13.4 | 7662 | 12.7 | −0.5 | −0.8 | −1.5 (−2.4 to −0.6) | 0.0012 | 0.0 | 0.84 |
Woken with chest tightness | 23 | 14 365 | 14.3 | 6420 | 12.6 | −0.5 | −0.7 | −1.3 (−3.0 to 0.3) | 0.1 | 57.6 | 0.00033 |
Woken with shortness of breath | 28 | 14 361 | 6.3 | 7459 | 5.5 | 0.3 | 0.4 | 0.9 (−0.1 to 2.0) | 0.071 | 50.6 | 0.0013 |
Woken by attack of coughing | 21 | 14 752 | 28.6 | 6279 | 27.8 | −0.4 | 0.5 | 0.2 (−2.3 to 2.6) | 0.91 | 65.0 | 0.000019 |
Asthma attack | 29 | 14 745 | 3.9 | 7694 | 3.5 | 0.7 | 0.1 | 0.6 (0.1 to 1.1) | 0.013 | 0.0 | 0.89 |
Current asthma medication | 27 | 14 749 | 4.0 | 7069 | 3.5 | 2.0 | 1.5 | 3.6 (3.0 to 4.2) | 3.6×10−31 | 0.0 | 0.56 |
Diagnosed asthma | 27 | 14 711 | 5.5 | 7002 | 4.8 | 2.0 | 1.5 | 3.5 (2.9 to 4.2) | 2.6×10−25 | 0.0 | 0.94 |
Nasal allergies | 27 | 14 279 | 24.8 | 7020 | 23.2 | 2.8 | −0.0 | 2.7 (1.7 to 3.7) | 1.2×10−7 | 0.0 | 0.8 |
Symptom from interviewer survey on a subsample | |||||||||||
Chronic winter cough | 26 | 14 698 | 7.7 | 4570 | 7.1 | −0.3 | 1.4 | 1.1 (−0.3 to 2.5) | 0.13 | 49.1 | 0.0027 |
Chronic winter phlegm | 26 | 14 665 | 6.3 | 4545 | 5.8 | 0.4 | 0.6 | 1.0 (−0.3 to 2.2) | 0.12 | 40.1 | 0.019 |
All estimates for change during the first 10 years of follow-up were compatible with estimates published in Chinn et al 1 (which were unadjusted for non-response, and included some centres which did not take part in ECRHS III).
*Crude prevalence in all target sample participants who completed postal survey in ECRHS I.
Numbers are in bold if p<0.05.
ECRHS, European Community Respiratory Health Survey.
Note that changes in estimates from ECRHS I to ECRHS III are not the sum of changes from ECRHS I to ECRHS II, and from ECRHS II to ECRHS III due to the use of inverse variance weighting required by DerSimonian and Laird meta-analysis.12