Abstract
The value of PEFR measurements in diagnosing reversible obstructive airway disease is debatable, therefore spirometry should be available on-site in the primary care practice. Measurements of FEV(1) and FVC (basic spirometry) are justified when the physician observes changes in the patient's pulmonary status. We assessed the validity of measurements of FEV(1) and FVC in 57 adult patients with limited airflow (FEV(1) range 0,84L-3,90 L) by 6 experienced GPs with the use of a hand held spirometer without a flow-volume loop visible on the display. The coefficient of variation of repeated measurements by the GP's was 2,1% for FEV(1) and 2,0% for FVC. The mean of the difference between FEV(1) measured by the GP's and FEV(1) measured by the lung function assistant with a pneumotachometer was 0,070 L. In all more severely obstructed patients ( FEV(1)<70% pred., N=33) difference between the values of FEV(1) and FVC by GP's and the golden standard was 0,100 L and 0,200 L at maximum respectively. The GP's measurement of the FEV(1) can be used interchangeably with the results of the lung function laboratory. Our further results indicate that validity of the FVC measured by the experienced GPs is negatively influenced by instrument- and not primarily by physician-elated factors.