Table 4.
Estimated equations of the 95th , 90th , 75th and 50th percentiles of methacholine slope given age and pretest level of FEV1 (litres), SAPALDIA cross-sectional study, 1991
| Slope95 | = | 34.70 | - | 0.0167 | age | - | 9.001 | FEV1 | + | 0 | FEV12 | (FEV1≤2.93) |
| = | 65.69 | - | 0.0167 | age | - | 30.152 | FEV1 | + | 3.6095 | FEV12 | (2.93<FEV1≤4.14) | |
| = | 3.82 | - | 0.0167 | age | - | 0.266 | FEV1 | + | 0 | FEV12 | (FEV1>4.14) | |
| Slope90 | = | 14.81 | - | 0.0160 | age | - | 3.523 | FEV1 | + | 0 | FEV12 | (FEV1≤2.93) |
| = | 26.48 | - | 0.0160 | age | - | 11.483 | FEV1 | + | 1.3584 | FEV12 | (2.93<FEV1≤4.14) | |
| = | 3.19 | - | 0.0160 | age | - | 0.236 | FEV1 | + | 0 | FEV12 | (FEV1>4.14) | |
| Slope75 | = | 4.90 | - | 0.0056 | age | - | 0.997 | FEV1 | + | 0 | FEV12 | (FEV1≤2.93) |
| = | 7.53 | - | 0.0056 | age | - | 2.796 | FEV1 | + | 0.3071 | FEV12 | (2.93<FEV1≤4.14) | |
| = | 2.27 | - | 0.0056 | age | - | 0.253 | FEV1 | + | 0 | FEV12 | (FEV1>4.14) | |
| Slope50 | = | 3.03 | - | 0.0039 | age | - | 0.642 | FEV1 | + | 0 | FEV12 | (FEV1≤2.93) |
| = | 4.77 | - | 0.0039 | age | - | 1.828 | FEV1 | + | 0.2025 | FEV12 | (2.93<FEV1≤4.14) | |
| = | 1.30 | - | 0.0039 | age | - | 0.152 | FEV1 | + | 0 | FEV12 | (FEV1>4.14) | |