Reproducibility of physical activity recall over fifteen years: longitudinal evidence from the CARDIA study

BACKGROUND: To examine the benefits of physical activity (PA) on diseases with a long developmental period, it is important to determine reliability of long-term PA recall. METHODS: We investigated 15-year reproducibility of PA recall. Participants were 3605 White and African-American adults in the Coronary Artery Risk Development in Young Adults study, aged 33–45 at the time of recall assessment. Categorical questions assessed PA before and during high school (HS) and overall PA level at Baseline, with the same timeframes recalled 15 years later. Moderate- and vigorous-intensity scores were calculated from reported months of participation in specific activities. RESULTS: HS PA recall had higher reproducibility than overall PA recall (weighted kappa = 0.43 vs. 0.21). Correlations between 15-year recall and Baseline reports of PA were r = 0.29 for moderate-intensity scores, and r = 0.50 for vigorous-intensity. Recall of vigorous activities had higher reproducibility than moderate-intensity activities. Regardless of number of months originally reported for specific activities, most participants recalled either no activity or activity during all 12 months. CONCLUSION: PA recall from the distant past is moderately reproducible, but poor at the individual level, among young and middle aged adults.