Construct validity of physical activity and sedentary behaviors staging measures for adolescents

Purpose: To evaluate the construct validity of physical activity (PA) and sedentary behaviors (SB) staging measures for adolescents that incorporate the current national recommendations. Method: The Progressive Aerobic Cardiovascular Endurance Run, Actigraph accelerometer and self-reported hours of TV viewing served as criterion measures. Participants were 878 adolescents (M age = 12.74, 53.6% girls, 39.9% non-White). Results: The PA staging measure had mixed evidence of convergent validity and strong evidence of divergent validity. The SB staging measure had strong and generalized evidence of convergent validity but weak evidence of divergent validity, which could be related to inaccurate assumptions about the relation of SB to PA and fitness. Results were generally in the expected direction and provide preliminary evidence for the construct validity and generalizability of both staging measures. However more research is warranted to validate the staging measures with Actigraph-measured PA and sedentary time. Effect sizes (112 values) ranged from small to large (.02-63). Conclusion: PA and SB stage-of-change measures that are congruent with current national recommendations and appropriate for use among adolescents were partially supported for their construct validity.