The Twin Cities Walking Study measured the associations of built environment versus socioeconomic and psychosocial variables with total physical activity and walking for 716 adults.
This article reports on the test–retest reliability of the survey portion of the study. To test the reliability of the study measures, 158 respondents completed measures twice within 1 to 4 weeks. Agreement between participants’ responses was measured using Pearson r and Spearman rho, and kappa statistics.
Demographic questions are highly reliable (R > .8). Questions about environmental and social features are typically less reliable (rho range = 0.42– 0.91). Reliability of the International Physical Activity Questionnaire (last 7 days version) was low (rho = 0.15 for total activity).
Much of the survey has acceptable-to-good reliability. The low test–retest reliability points to potential limitations of using a single administration of the IPAQ to characterize habitual physical activity. Implications for sound inference are accordingly complicated.
Forsyth is with the Dept of City and Regional Planning, Cornell University, Ithaca, NY 14853. Oakes is with the Division of Epidemiology, University of Minnesota, Minneapolis, MN 55454. Schmitz is with the Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania, Philadelphia, PA 19104.