Purpose: The purpose of this study was to explore the validity of the Assessment of Young Children's Activity Using Video Technology (ACTIVITY) self-report instrument in assessing previous-day physical activity.
Methods: Forty-seven third-grade children (mean age 7.72 +/- 0.45, 41% female) from one elementary school completed the ACTIVITY on one weekday. To evaluate concurrent validity, children wore a Caltrac accelerometer and a Polar Vantage XL heart rate monitor on the day before completing the ACTIVITY. An ACTIVITY score from six time-anchored questions was obtained from the ACTIVITY. Mean Caltrac counts per minute (CNTSMIN), average activity heart rates, and cumulative minutes at or above 50% of heart rate reserve (50% HRR) were calculated for the entire day (7:00 a.m. to 7:00 p.m.).
Results: Significant Pearson product-moment correlations were observed between the ACTIVITY score and CNTSMIN (r = 0.40, P < 0.001) and 50% HRR (r = 0.50, P < 0.001). Answers from four of six time-anchored questions correlated significantly with heart rate scores during those time periods (r = 0.30-0.49).
Conclusions: This exploratory study suggests that the ACTIVITY self-report instrument is a moderately valid instrument for measuring general activity levels of young children during the school year, including during specified periods of time. The potential for video technology to facilitate accurate physical activity recall in young children warrants further study.