title: Longitudinal study of free running exercise challenge: reproducibility.
abstract: The reproducibility of free running exercise challenge has been examined in an unselected population of 8-10 year olds. Using a standardised protocol, monthly exercise tests were performed on 143 children over one year. A positive test was defined using both a 15% and 20% fall in peak expiratory flow after exercise. The mean (95% confidence interval, CI) population frequency for a positive test at 15% fall was 14.9% (6.5 to 23.3) and coefficient of variation 24.6%. For a 20% fall, the mean (95% CI) population frequency was 7.9% (2.9 to 12.9) and coefficient of variation 27.8%. Seventy two (50.3%) of the children gave at least one positive response at 15% fall. Exercise testing is not reproducible in the community setting and should not be used as a screening test. Exercise data from epidemiological studies of asthma should be interpreted with caution.
authors.affiliation: University Department of Paediatrics, Children's Hospital, Sheffield.
authors.forename: C V
authors.initials: CV
authors.lastname: Powell
authors.forename: R D
authors.initials: RD
authors.lastname: White
authors.forename: R A
authors.initials: RA
authors.lastname: Primhak
mesh_terms: D001249:Asthma / Q000503:physiopathology / Q000517:prevention & control*; D002648:Child; D003430:Cross-Sectional Studies; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008403:Mass Screening / Q000379:methods*; D010366:Peak Expiratory Flow Rate; D015203:Reproducibility of Results; D012420:Running / Q000502:physiology*