Computer-assisted techniques may be a useful way to enhance physical activity surveillance and increase accuracy of reported behaviors.
Evaluate the reliability and validity of a physical activity (PA) self-report instrument administered by telephone and internet.
The telephone-administered Active Australia Survey was adapted into 2 forms for internet self-administration: survey questions only (internet-text) and with videos demonstrating intensity (internet-video). Data were collected from 158 adults (20–69 years, 61% female) assigned to telephone (telephone-interview) (n = 56), internet-text (n = 51), or internet-video (n = 51). Participants wore an accelerometer and completed a logbook for 7 days. Test-retest reliability was assessed using intraclass correlation coefficients (ICC). Convergent validity was assessed using Spearman correlations.
Strong test-retest reliability was observed for PA variables in the internet-text (ICC = 0.69 to 0.88), internet-video (ICC = 0.66 to 0.79), and telephone-interview (ICC = 0.69 to 0.92) groups (P-values < 0.001). For total PA, correlations (ρ) between the survey and Actigraph+logbook were ρ = 0.47 for the internet-text group, ρ = 0.57 for the internet-video group, and ρ = 0.65 for the telephone-interview group. For vigorous-intensity activity, the correlations between the survey and Actigraph+logbook were 0.52 for internet-text, 0.57 for internet-video, and 0.65 for telephone-interview (P < .05).
Internet-video of the survey had similar test-retest reliability and convergent validity when compared with the telephone-interview, and should continue to be developed.
Creamer (firstname.lastname@example.org), Pettee Gabriel, and Kohl are with the Dept of Epidemiology, Human Genetics, and Environmental Sciences, University of Texas School of Public Health, Austin, TX. Bowles is with the Risk Factor Monitoring and Methods Branch, National Cancer Institute, Washington, DC. von Hofe and Bauman are with the School of Public Health, University of Sydney, Camperdown, NSW, Australia.