Prediction equations for the fifth percentiles of lung function variables
| Equation | |
| Males | |
| FVC L | exp(-10.437+2.280 ln(H)+0.00532A-0.000124A2) |
| FEV1 L | exp(-9.111+2.014 ln(H)+0.00102A-0.000105A2) |
| MEF75 L·s−1 | exp(-2.524+0.812 ln(H)+0.00661A-0.000132A2) |
| MEF50 L·s−1 | exp(-3.338+0.911 ln(H)-0.00289A-0.000109A2) |
| MEF25 L·s−1 | exp(-4.262+1.009 ln(H)-0.02485A-0.000020A2) |
| FEV1/FVC % | exp(+6.180-0.341 ln(H)-0.00529A+0.000026A2) |
| PEF L·s−1 | exp(-3.992+1.170 ln(H)+0.00493A-0.000110A2) |
| Females | |
| FVC L | exp(-9.213+2.013 ln(H)+0.00616A-0.000155A2) |
| FEV1 L | exp(-8.521+1.865 ln(H)+0.00357A-0.000150A2) |
| MEF75 L·s−1 | exp(-2.977+0.867 ln(H)+0.00698A-0.000140A2) |
| MEF50 L·s−1 | exp(-2.374+0.674 ln(H)+0.00330A-0.000180A2) |
| MEF25 L·s−1 | exp(-5.140+1.145 ln(H)-0.02002A-0.000096A2) |
| FEV1/FVC % | exp(+5.524-0.219 ln(H)-0.00313A+0.000004A2) |
| PEF L·s−1 | exp(-5.032+1.316 ln(H)+0.00767A-0.000143A2) |
FVC: forced vital capacity; FEV1: forced expiratory volume in one second; MEF25 or 50 or 75: maximal instantaneous forced expiratory flow when 25, 50 or 75% of the FVC remains to be exhaled, respectively; PEF: peak expiratory flow; H: height (cm); A: age (yrs); exp(x): ex. #: fraction of explained variance.