Start of test | Within-test | End of test | Repeatability |
Rapid rise to peak expiratory flow Back extrapolated volume < 12.5% FVC or 80 ml (whichever is greater) | Smooth expiration, no glottic closure or cough No leak or obstruction of mouthpiece No early inspiration | Plateau reached on volume time curve Cessation of flow must not occur at 10% peak flow (but may be able to report FEVt) | 2 manoeuvres within 0.1 L or 10% highest value for FVC and FEVt 1 manoeuvre may be reported if acceptable but this should be clearly stated |
Data are adapted from [37].