Reliability and validity of a single-item physical activity measure for adolescents

• Published in: Journal of paediatrics and child health Vol. 51; no. 8; pp. 787 - 793
• Main Authors: Scott, Joseph J, Morgan, Philip J, Plotnikoff, Ronald C, Lubans, David R
• Format: Journal Article
• Language: English
• Published: Australia Blackwell Publishing Ltd 01.08.2015
• Subjects: Adolescent; Exercise; Female; Humans; Male; Motor Activity; New South Wales; Pediatrics; physical activity; questionnaire; Reproducibility of Results; self-report; Surveys and Questionnaires - standards; Teenagers; youth; New South Wales; adolescent; questionnaire; self-report; youth; physical activity
• ISSN: 1034-4810; 1440-1754; 1440-1754
• DOI: 10.1111/jpc.12836

Aims The aim of this study was to examine the test–retest reliability and concurrent validity of an adolescent single‐item physical activity measure by comparing it with the existing Oxford Physical Activity Questionnaire (OPAQ) and accelerometer output. Methods Participants were 123 adolescents (14.7 ± 0.5 years) from three secondary schools in New South Wales, Australia. To determine reliability, participants completed both questionnaires on two occasions separated by 2 weeks. To assess validity, participants wore Actigraph GT3X+ accelerometers for a 7‐day monitoring period and completed both physical activity questionnaires. Bivariate correlations between self‐reported moderate‐to‐vigorous physical activity (MVPA) and accelerometer MVPA min/day were calculated. Results The single‐item (intra‐class correlation coefficient (ICC) = 0.75, 95% confidence interval (CI) = 0.64–0.83, P < 0.001) ) and the OPAQ (ICC = 0.79, 95% CI = 0.69–0.86, P < 0.001) were both found to have moderate‐to‐strong reliability. Correlations between self‐reported and objectively measured MVPA were similar for the single‐item measure (r = 0.44, 95% CI = 0.24–0.63, P < 0.001) and the OPAQ (r = 0.50, 95% CI = 0.30–0.65, P < 0.001). Conclusions These findings suggest the single‐item measure can provide a reliable and valid assessment of youth physical activity.