Factor structure and psychometric properties of a perceived barriers to physical activity scale for low-income teens

Background: Despite known benefits of health and well-being, high-school aged adolescents don’t engage in regular daily physical activity (PA). PA levels are lesser among low-income adolescents. One significant predictor of PA levels is perceived barriers, however, there is a lack of a valid and reliable scale to measure perceived barriers among the low-income adolescent population. The objective of this study was to develop a scale to assess perceived barriers to PA among these high-school aged, low-income adolescents. Methods: The Perceived Barriers to PA Survey for Low-Income Adolescents (PBPA-A) was developed using a mixed-method approach. Initially, 110 items were identified from pre-existing surveys and extensive literature review. These items were then tested using cognitive interviews (n=15) to ensure the wording clarity and appropriateness. Items were deleted and revised based on the feedback from the cognitive interviews. Then, a 2-week test-retest reliability was conducted with 105 adolescents to assess the scale’s consistency over time using intraclass correlation coefficient (ICC). Items with ICC ≤ 0.4, indicating insufficient reliability, were deleted, as were those demonstrating a floor effect. Exploratory factor analysis (n=999) and confirmatory factor analysis (n=999) were used to explore and confirm the underlying structure of the remaining 73-item scale. Items with a loading of ≥0.4 were retained and internal consistencies for the whole scale and subscales were calculated using Cronbach’s alpha. Test-retest reliability was recalculated, and concurrent validity was tested in a sample of 1,998 adolescents against the pre-established physical activity questionnaire for adolescent (PAQ-A) using Spearman correlations.Results: The EFA yielded a 7-factor solution with 37 items, which was further cross-validated by CFA. The test-retest reliability was 0.75 for the whole scale and ranged from 0.65 to 0.81 for the subscales. As predicted, the PABA-A scale and subscales were negatively associated the PAQ-A score, indicating adolescents with higher perceived barriers had lower physical activity levels. Conclusions: The PBPA-A is a valid and reliable scale that can be used to measure perceived barriers among older, low-income adolescents to better understand the relationship between perceived barriers and PA in this population. Further research is warranted to validate the scale in other adolescent subgroups.