Effect of Accelerometer Cut-Points on Preschoolers' Physical Activity and Sedentary Time: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aimed to compare estimated levels of physical activity (PA) and sedentary time (ST) of preschool-aged children (3-5 years old) based on different published accelerometer cut-points used in this age group. Four electronic databases were searched to identify studies estimating levels of PA or ST (ST, light PA [LPA], and moderate to vigorous PA [MVPA]) using multiple accelerometer cut-points, in a sample of preschool-aged children. Data were extracted and risk of bias assessed for all included studies. Random-effects meta-analysis was used to estimate pooled effects for unique combinations of accelerometer cut-points for each outcome. Twenty-four studies, reporting on 18 unique samples, were included. Results demonstrated substantial variability in estimates of PA and ST across different cut-points, with significant differences in estimates of the behaviors between most cut-points. Few cut-points showed similarity; Evenson and Pate were some of the most similar for the assessment of PA and ST of young children. However, when calculating the differences in ST, LPA, and MVPA between the cut-points, the Evenson cut-point estimates approximately 60 min more LPA per day and the Pate 148CPM cutpoints estimates 23 and 37 min more ST and MVPA each day, respectively. Given that these were the most similar estimates, this highlights the magnitude of differences between the accelerometer cut-points when estimating preschool-aged children's movement behavior. This review provides an illustration on the limitations of accelerometer cut-points used to determine PA and ST of preschool-aged children; in that they often produce substantially different estimates. This review provides a compelling rationale as to why further research moving toward alternative data processing methodologies is required, including to identify an optimal approach to estimating movement behavior outcomes in young children that considers congruence with past and future