Table 3 Quality control in pre-school spirometry, adapted from [37]
Start of testWithin-testEnd of testRepeatability
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 inspirationPlateau 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].