title: Comparison of a video questionnaire with the IUATLD written questionnaire for measuring asthma prevalence.
abstract: A video questionnaire (VQ) for measuring asthma prevalence in adolescents was assessed for repeatability and validity in relation to bronchial hyperresponsiveness (BHR) (PD20 less than or equal to 7.8 mumol methacholine). Comparison was also made with a standard, self completed written questionnaire (SQ), based on the IUATLD Bronchial Symptoms Questionnaire, which included five questions seeking comparable data to those in the VQ. Both the VQ and SQ were administered to 707 schoolchildren (13-16 years), in whom English was the primary language. One hundred and six randomly selected children subsequently underwent bronchial challenge to methacholine. Both the sensitivity and specificity for BHR were higher for a combination of three or more positive responses to the VQ (0.73 and 0.88), than to the SQ (0.63 and 0.82), although these differences were not statistically significant (P = 0.24). When administered again after a two week interval, the VQ had a significantly higher (P = 0.03) coefficient of repeatability (0.79) than the SQ (0.50). We conclude that the VQ is a valid and reliable method of determining asthma prevalence, and propose that by providing data relatively free from biases due to language, culture, literacy or interviewing techniques it may be particularly useful when comparing asthma prevalence and severity in different populations.
authors.affiliation: Department of Medicine, Wellington School of Medicine, New Zealand.
authors.forename: R A
authors.initials: RA
authors.lastname: Shaw
authors.forename: J
authors.initials: J
authors.lastname: Crane
authors.forename: N
authors.initials: N
authors.lastname: Pearce
authors.forename: C D
authors.initials: CD
authors.lastname: Burgess
authors.forename: P
authors.initials: P
authors.lastname: Bremner
authors.forename: K
authors.initials: K
authors.lastname: Woodman
authors.forename: R
authors.initials: R
authors.lastname: Beasley
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000175:diagnosis / Q000453:epidemiology*; D001985:Bronchial Provocation Tests; D003625:Data Collection; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008297:Male; D009520:New Zealand / Q000453:epidemiology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires; D014743:Videotape Recording