Do subjects investigated for occupational asthma through serial peak expiratory flow measurements falsify their results?
GROUND AND AIM: Serial assessment of peak expiratory flow (PEF) rates has been advocated as a sensitive and specific means of investigating occupational asthma. The possibility that, for several reasons, subjects do not accurately report their values has been raised. The availability of portable instruments that assess PEF and store timings and values now make it possible to estimate compliance and accuracy of results. METHODS: Twenty-one subjects consecutively investigated for occupational asthma were asked to assess their PEF every 2 hours during the day, both at work and away from work, with a VMX instrument (Clement Clarke International, Columbus, Ohio) and record the times and values on a sheet of paper. The subjects were not aware that the data were also being stored on a computer chip. The diagnosis was occupational asthma in eight subjects, personal asthma in four subjects, and neither condition in nine subjects. RESULTS: The mean duration of recording was 36 days (range, 14 to
Related Questions
- What is the feasibility of obtaining serial measurements of peak flow in workers suspected of having occupational asthma?
- Do long periods off work in peak expiratory flow monitoring improve the sensitivity of occupational asthma diagnosis?
- How many times per day should peak expiratory flow rates be assessed when investigating occupational asthma?
