The % predicted corresponding with the 5th percentile and the one sided 95% CI for different equations, black miners only
| Age | n | Mean | SD | Skewness | Predicted equation | Louw's equation | ECCS equation | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 5th Percentile | 95% CI | 5th Percentile | 95% CI | 5th Percentile | 95% CI | ||||||||||||||
| FVC: | |||||||||||||||||||
| <30 | 1692 | 99.2 | 11.8 | 0.07 | 80.6 | 79.7 | 78.7 | 78.0 | 72.6 | 72.0 | |||||||||
| 30–39 | 7430 | 100.6 | 12.4 | 0.17 | 80.9 | 80.2 | 78.9 | 78.2 | 73.8 | 73.0 | |||||||||
| 40–49 | 4947 | 100.8 | 13.7 | 0.15 | 79.5 | 78.3 | 77.2 | 76.1 | 73.4 | 72.1 | |||||||||
| ⩾50 | 1704 | 99.9 | 14.6 | 0.07 | 76.1 | 75.8 | 73.6 | 73.3 | 71.7 | 70.8 | |||||||||
| FEV1: | |||||||||||||||||||
| <30 | 1692 | 99.6 | 12.3 | −0.22 | 80.4 | 79.4 | 82.5 | 81.7 | 76.7 | 75.7 | |||||||||
| 30–39 | 7430 | 100.1 | 13.1 | −0.01 | 78.9 | 78.5 | 80.7 | 80.3 | 75.2 | 74.9 | |||||||||
| 40–49 | 4947 | 99.9 | 15.0 | −0.17 | 75.3 | 75.2 | 76.3 | 76.3 | 71.8 | 71.7 | |||||||||
| ⩾50 | 1704 | 99.9 | 16.8 | 0.23 | 71.3 | 72.4 | 71.2 | 72.7 | 68.0 | 68.9 | |||||||||
| FEV1%: | |||||||||||||||||||
| <30 | 1692 | 100.5 | 7.0 | −0.68 | 88.5 | 89.0 | NA | NA | 94.6 | 95.0 | |||||||||
| 30–39 | 7430 | 99.9 | 7.3 | −0.74 | 87.3 | 87.9 | NA | NA | 92.6 | 93.3 | |||||||||
| 40–49 | 4947 | 99.8 | 8.5 | −0.94 | 84.9 | 85.9 | NA | NA | 89.3 | 90.6 | |||||||||
| ⩾50 | 1704 | 100.6 | 9.7 | 0.97 | 82.5 | 84.7 | NA | NA | 86.3 | 88.6 | |||||||||