Wdf. Smith et al., EVALUATION OF THE VMM TURBINE FOR SPIROMETRY IN THE APPLIED PHYSIOLOGY LABORATORY, Canadian journal of applied physiology, 18(3), 1993, pp. 317-324
The volume measurement module turbine (VMM) was evaluated in 51 subjec
ts for spirometry in applied physiology against the Stead-Wells spirom
eter (SW) and Wright peak flow meter (WM). The volume and flow ranges
(VMM) were, FEV1 1.32 to 3.94 L (mean 2.62, confidence interval [CI] 2
.46 to 2.78); forced vital capacity (FVC) 1.97 to 5.06 L (mean 3.50, C
I 3.29 to 3.71); and peak expiratory flow rate (PEFR) 290 to 624 L.min
-1 (mean 434, CI 407 to 461). The mean difference for FEV1 was 0.09 L
(CI 0.05 to. 0.14), FVC 0.04 L (CI -0.02 to 0.10), and PEFR 18.0 L min
-1 (CI 8.7 to 27.3) less than SW or WM. Bias with FEV1 and FVC was not
significant, though PEFR demonstrated a significant proportional erro
r. The repeatability coefficients for FEV1 and FVC were 0.18 and 0.20,
comparable to the SW; but for PEFR they were greater, 58.4 versus 33.
8 L.min-1 by WM. The VMM turbine is accurate and reliable for the meas
urement of FEV1 and FVC over the ranges studied; however, care should
be taken when interpreting PEFR.