A Domain-Specific Approach for Assessing Physical Activity Efficacy in Adolescents: From Scale Conception to Predictive Validity

Enhancing the Content Validity of Self-Reported Physical Activity Self-Efficacy in Adolescents: A Qualitative Study

PURPOSE

This study's primary purpose was to enhance the content validity of a self-reported measure of self-efficacy for physical activity (PA) in adolescents. This was addressed through assessment of younger and older adolescents' understanding of the construct of self-efficacy for PA, coupled with assessment of the content coverage and comprehensibility of items derived from existing measures.

METHODS

Participants completed individual semistructured and cognitive debriefing interviews as well as 3 PA self-efficacy questionnaires.

RESULTS

Thematic analysis identified personal and environmental facilitators and barriers to PA self-efficacy. The major categories were physical; psychological; interaction with surroundings; support and relationships; attitudes; and services, systems, and natural environments. Cognitive interviews resulted in the retention of 52 final items: 24 for self-efficacy with perceived facilitators and 28 for self-efficacy to overcome barriers.

CONCLUSIONS

This study provides a PA self-efficacy instrument with expanded content coverage that is relevant to adolescents as young as 11 years. With further validation testing in future studies, this instrument will enable pediatric physical therapists and researchers to assess PA self-efficacy and design effective intervention strategies to improve PA.