Validity and reliability of scales measuring social support and self‐efficacy for physical activity in students

Abstract

Objective: To examine the validity and reliability (reproducibility and internal consistency) of scales of social support and self‐efficacy for physical activity in nine to fifteen‐year‐old students.

Methods: The study included 1.678 students in the validity and internal consistency phase and 1.393 students during the reproducibility. Students of both sexes aged nine to fifteen years, from the city of Curitiba, Brazil, participated in the study. The validity was verified by the exploratory factor analysis, the reproducibility by the intraclass correlation coefficient and the internal consistency by the Cronbach's alpha.

Results: The scales of social support and self‐efficacy for physical activity showed two factors with factor loadings equal to or greater than 0.40 for all ages. The reproducibility scores were adequate in all age groups for the social support measures for physical activity (≥ 0.81) and self‐efficacy measures for physical activity (≥ 0.72). The internal consistency for the social support scale ranged from 0.87 to 0.90 and from 0.77 to 0.82 for the self‐efficacy scale.

Conclusions: The scales showed satisfactory factorial validity and adequate reproducibility and internal consistency being, suitable for students aged nine to fifteen.