The Development And Testing Of A Direct Observation Protocol For Children’S Free-play Activity

Abstract

Traditional real-time direct observation (DO) systems have been used for decades to assess children’s free-living physical activity (PA). Using video-taped DO would overcome several methodological issues and allow for more precise assessments of behaviors. PURPOSE: To develop and test a novel video-based DO system for children’s free-play activity. METHODS: Following iterative DO system development (The Observer XT, Noldus), 28 children (age=8.4±1.5 years) participated in a 30-minute indoor free-play session. The participants were recorded using a GoPro camera and wore an accelerometer on the hip (AG-H) and non-dominant wrist (AG-W). Researchers coded videos for the main Whole-Body Movement and four modifiers: 1) Locomotion, 2) Limb Movement, 3) Activity Type, and 4) MET value. For intrarater reliability, percent agreement was calculated from six randomly selected videos, using duplicate entries by an expert coder one-week apart. For inter-rater reliability, three videos were used to calculate percent agreement between entries from trained, novice coders (n=6) and the expert coder. To assess construct validity, time spent in activity intensity categories from expert-coded DO MET values were compared with accelerometer estimates using Wilcoxon Rank-Sum tests. RESULTS: Percent agreement for intra-rater reliability was above 80% except for Locomotion (47%; video 4, 26%; video 3) and Limb Movement, and MET value (19%, 78%, respectively; video 3). Across all variables, percent agreement for inter-rater reliability ranged widely from 12%-96%, 0-100%, and 36%-97% for videos 1, 2 and 3, respectively. Mean estimated time spent in PA intensity categories from AG-H overestimated sedentary (SED; p=0.008), moderate (MPA; p<0.001), and moderate-to-vigorous PA (MVPA; p=0.017) and underestimated light, (LPA; p< 0.001). The AG-W underestimated SED (p=0.03) and LPA (p<0.001) but overestimated MPA (p<0.001) and MVPA (p<0.001). CONCLUSIONS: The current DO system is feasible for observing detailed changes in children’s free-play activity. However, refinement to the system must be made to improve reliability before it is adopted as a criterion measure for free-play activity in children. Supported by: University of Massachusetts Amherst Commonwealth Honors College