A comparison of functional residual capacity measured by body plethysmography with that measured by
nitrogen washout reveals that the measurement obtained during the nitrogen washout test is less than that during body plethysmography. This discrepancy is most likely caused by which of the following?
a. Poor technique c. Restrictive lung disease
b. Severe air-trapping d. Directional valve malfunction
Question 2
The standard for repeatability for forced expiratory volume in 1 second (FEV1) is ___ mL.
a. 100 c. 200
b. 150 d. 250