Abstract
The mini-Wright peak flow meter (MPFM) has been evaluated, and the results obtained from it show a strong positive correlation (r=0.970) with the Wright's peak flow meter (PFM). MPFM measurements, however, were biased to be about 38 1/min higher than PFM measurements (95% confidence limits 31.01/min to 45.01/min). Between instrument variation was found (F--ratio 3.67 with 9 and 81 degrees of freedom: P less than 0.001). In practice this did not appreciably affect individual measurements greatly as 95% confidence limits on any individual measurements were increased from +/-24 1/min to +/-27 1/min. There was no significant day-to-day variability in measurements obtained with individual instruments. The MPFM is a pocket-sized, simple, cheap, and robust instrument for following changes in ventilatory function. In clinical trails and surveys, however, both the bias in favour of the MPFM compared to the PFM and inter-machine variation must be taken into account. As the manufacturers have altered the scale to remove the bias since this study was performed, it will be important to know whether the original or the modified meter is being used in future studies.
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- Bhoomkar A., Davies S., Greary M., Hills E. Comparison of peak flow gauge and peak flow meter. Thorax. 1975 Apr;30(2):225–227. doi: 10.1136/thx.30.2.225. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Haydu S. P., Chapman T. T., Hughes D. T. Pulmonary monitor for assessment of airways obstruction. Lancet. 1976 Dec 4;2(7997):1225–1225. doi: 10.1016/s0140-6736(76)91147-8. [DOI] [PubMed] [Google Scholar]
- Robertson D. G., Epstein S. W., Warrell D. A. Trial of disodium cromoglycate in bronchial asthma. Br Med J. 1969 Mar 1;1(5643):552–554. doi: 10.1136/bmj.1.5643.552. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Turner-Warwick M. On observing patterns of airflow obstruction in chronic asthma. Br J Dis Chest. 1977 Apr;71(2):73–86. doi: 10.1016/0007-0971(77)90086-9. [DOI] [PubMed] [Google Scholar]
- WRIGHT B. M., McKERROW C. B. Maximum forced expiratory flow rate as a measure of ventilatory capacity: with a description of a new portable instrument for measuring it. Br Med J. 1959 Nov 21;2(5159):1041–1046. doi: 10.1136/bmj.2.5159.1041. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ward F. G. Practical pulmonary function testing. J Soc Occup Med. 1977 Oct;27(4):138–142. doi: 10.1093/occmed/27.4.138. [DOI] [PubMed] [Google Scholar]