Measurement of NSTT was performed both before and after VCPT.
As with NSTT, we saw no difference in baseline or post-VCPT EBC [NO.sub.x] values between normal subjects and subjects with stable CF (P = 0.09).
In this model, we use NSTT as a surrogate of mucociliary clearance.
Although our study groups were small in number, the effect of percussion on nasal clearance was quite striking with both biologically relevant and statistically significant changes in NSTT.
The NSTT is, however, a direct functional measure of mucociliary clearance of the upper airway.