Comparison of Exercise Vital Sign Screening with Accelerometer Data to Assess Adolescent Physical Activity: A Pilot Study

ABSTRACT Introduction Physical activity levels can be difficult to quantify clinically. Accelerometers provide objective data but are not universally worn. Physical activity screening estimates the minutes of activity provided by the patient. The goal of this study was to compare subjective Exercise Vital Sign (EVS) screening data to objectively measured accelerometry data and evaluate correlations of both measures in adolescents. Methods Sixty-nine adolescents aged 12–18 yr were recruited from outpatient sports medicine clinics and a local high school. All participants completed EVS screening, which consisted of two questions estimating moderate-to-vigorous physical activity (MVPA). Participants also wore an accelerometer for 7 d to capture physical activity. Physical activity data from EVS and accelerometry were compared using the Spearman correlation coefficients. The comparability of activity was evaluated using simple and weighted κ statistics. Sensitivity, specificity, and positive and negative predictive values were also calculated for EVS. Results A weak correlation was found between EVS and accelerometry data ( ρ = 0.26, P = 0.03). A low agreement was observed between activity categories (weighted κ = 0.10), with a higher concordance observed using the dichotomous variable of physical activity (unweighted κ = 0.15). The sensitivity, specificity, and positive and negative predictive values were 13%, 98%, 67%, and 79%, respectively, using EVS screening for physical activity. Conclusions Overall, a weak positive correlation was demonstrated between EVS screening and accelerometry. EVS screening demonstrated a high specificity (98%) for identifying insufficient MVPA. EVS screening is a tool with applications in pediatric clinical settings that might prompt healthcare providers to promote physical activity to improve health and wellbeing.