Notice: Users may be experiencing issues with displaying some pages on stanfordhealthcare.org. We are working closely with our technical teams to resolve the issue as quickly as possible. Thank you for your patience.
 

Learn about the flu shot, COVID-19 vaccine, and our masking policy »

Stanford Health Care

Truncating the dose range for methacholine challenge tests: Three occupational studies JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL MEDICINE Agalliu, I., Eisen, E. A., Hauser, R., Redlich, C. A., Stowe, M. H., Cullen, M. R., Wegman, D. H., CHRISTIANI, D. C., Kennedy, S. M. 2003; 45 (8): 841-847

Abstract

The methacholine challenge test protocol was assessed in the reanalysis of three occupational studies. We evaluated the impact of truncating the range of methacholine on responsiveness, as defined by slope and PC(20). In original analysis, reactivity was similar for apprentices and auto body shop workers, whereas boilermakers were more responsive. Truncating high concentrations did not change the classification of subjects with PC(20) <8 or 16 in any population. However, when responsiveness was measured by slope, the mean responsiveness increased, from -7.9 to -15.3 for apprentices and -7.2 to -10.0 for auto-body shop workers. Results support the American Thoracic Society's recommended maximum of 16 mg/ml and provide evidence that extending the dose range beyond that does not increase sensitivity, whereas stopping before 16 may exaggerate response. Furthermore, to ensure validity, neither slope nor PC(20) should be extrapolated beyond data.

View details for DOI 10.1097/01.jom.0000083031.56116.53

View details for Web of Science ID 000184777400009

View details for PubMedID 12915785