[Investigation on quality of spirometry in 36 large hospitals in China]

To assess the current status of quality control of spirometry reports in China.

Spirometry case reports from January 2008 to October 2008 were collected from pulmonary function testing laboratories in 36 large hospitals (provincial or municipal) in China. The quality analysis was performed according to ATS/ERS standardization for measurement of spirometry. The number of reports that met the criteria for quality control was expressed as percentages.

A total of 345 spirometry test reports were collected. 82.5% (282/342) met the start-of-test criteria for quality control. 333 reports could be analyzed for free of artifacts, of which 65.8% (219/333) were consistent with the criteria of smooth expiration; the remaining reports (114) failed to meet the criteria, for reasons including cough (29/333, 8.7%), premature glottis closure (8/333, 2.4%), gas leakage (29/333, 8.7%), early termination of expiration (26/333, 7.8%), mouthpiece obstruction (6/333, 1.8%), and incomplete exertion of efforts (49/333, 14.7%). 235 reports were analyzed for end-of-test criteria, with 50.6% (119/235) complying to criteria. 22.6% (78/345) of the reports were tested for more than 3 times, among which 65 reports with the data of each manoeuvre could be analyzed for repeatability. 95.4% (62/65) of the reports met the repeatability criteria, which accounted for 18.0%(62/345)of the total reports collected. The rate of the 2 highest FVC (forced vital capacity) and FEV(1) (forced expiratory volume in one second) of less than 150 ml was 95.4% (62/65) and 100.0% (65/65), respectively. The rate of the 2 highest FVC and FEV(1) of less than 100 ml was 92.3% (60/65) and 87.7% (57/65), respectively. Only 7.2% of the reports (25/345) met all of the 4 criteria listed above.

The quality of spirometry tests in large (provincial or municipal) hospitals in China needs to be improved in the future.