Cut-points for response to mannitol challenges using the forced oscillation technique

The forced oscillation technique (FOT) can be used to determine airway hyperresponsiveness, but the cut-points for changes in respiratory system conductance (Grs) and reactance (Xrs) that define a positive mannitol challenge are not known. Furthermore, the effects of changes in lung volume on these cut-points or on the repeatability of the test are unknown.