title: Reliability and validity of an internet-based questionnaire measuring lifetime physical activity.
abstract: Lifetime exposure to physical activity is an important construct for evaluating associations between physical activity and disease outcomes, given the long induction periods in many chronic diseases. The authors' objective in this study was to evaluate the measurement properties of the Lifetime Physical Activity Questionnaire (L-PAQ), a novel Internet-based, self-administered instrument measuring lifetime physical activity, among Canadian men and women in 2005-2006. Reliability was examined using a test-retest study. Validity was examined in a 2-part study consisting of 1) comparisons with previously validated instruments measuring similar constructs, the Lifetime Total Physical Activity Questionnaire (LT-PAQ) and the Chasan-Taber Physical Activity Questionnaire (CT-PAQ), and 2) a priori hypothesis tests of constructs measured by the L-PAQ. The L-PAQ demonstrated good reliability, with intraclass correlation coefficients ranging from 0.67 (household activity) to 0.89 (sports/recreation). Comparison between the L-PAQ and the LT-PAQ resulted in Spearman correlation coefficients ranging from 0.41 (total activity) to 0.71 (household activity); comparison between the L-PAQ and the CT-PAQ yielded coefficients of 0.58 (sports/recreation), 0.56 (household activity), and 0.50 (total activity). L-PAQ validity was further supported by observed relations between the L-PAQ and sociodemographic variables, consistent with a priori hypotheses. Overall, the L-PAQ is a useful instrument for assessing multiple domains of lifetime physical activity with acceptable reliability and validity.
authors.affiliation: Arthritis Research Centre of Canada, Vancouver, British Columbia, Canada. mdevera@arthritisresearch.ca
authors.forename: Mary A
authors.initials: MA
authors.lastname: De Vera
authors.forename: Charles
authors.initials: C
authors.lastname: Ratzlaff
authors.forename: Paul
authors.initials: P
authors.lastname: Doerfling
authors.forename: Jacek
authors.initials: J
authors.lastname: Kopec
mesh_terms: D002170:Canada; D005260:Female; D006801:Humans; D020407:Internet; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D011998:Recreation; D015203:Reproducibility of Results; D012737:Sex Factors; D013177:Sports; D011795:Surveys and Questionnaires / Q000592:standards*; D013997:Time Factors