Scale development for perceived school climate for girls' physical activity

Despite considerable evidence that physical activity confers substantial health benefits, many adolescents do not engage in sufficient activity to meet minimum recommended levels.1,2 Physical activity (PA) declines during the transition from childhood to adolescence in both girls and boys.3–6 Boys generally engage in more PA at each age,6 and there is a sharp decline among teenage girls.7,8 Understanding the gender discrepancy can inform interventions promoting PA among girls. One of the few large-scale physical activity intervention studies in middle schools underscores this concern: investigators found that boys were more active than girls both during physical education (PE) classes9 and on school grounds during non-PE times.10 After 2 years of intervention, significant increases in PA were detected among boys but not girls.11 Because adolescents spend a substantial amount of time at school, this environment is of interest for understanding and modifying PA behaviors.12,13 The extent to which the school climate supports girls’ being physically active may be important. School climate has been described as the quality of the overall school environment, comprising 4 domains: physical environment, social system, culture, and aggregated characteristics of members of the school community.14,15 Each of these domains could potentially affect girls’ participation in PA, for example, through adequate PA facilities (physical environment), interpersonal relationships that are respectful of gender differences and social and pubertal development (social system), values and norms that support a physically active lifestyle for all (culture), and the prevalence of PA-related behaviors of other girls and female staff members in the school (aggregated characteristics). There is some evidence to support the hypothesis that general school climate or functioning affects students’ health behaviors such as use of tobacco, alcohol, or violence.16–18 Research also suggests that school-level norms specifically concerning alcohol or tobacco use are related to individual students’ substance use.19,20 To date, there has been less research into the effects of school climate on physical activity. School-level measures such as the recent School Health Index 21 will help facilitate investigations into the effects of school policies and physical environments on physical activity and other health behaviors. However, the School Health Index does not have an explicit gender focus, nor does it explicitly evaluate students’ perceptions of the culture regarding PA. A computerized literature search yielded no school climate survey measures specific to girls’ or to general PA. Qualitative research, however, supports the idea that girls perceive school climate regarding PA to be relevant to their PA participation both in PE classes22–24 and overall.25 The purpose of this study was to establish the factorial validity, factorial invariance, and construct validity of an original scale assessing perceived school climate for girls’ physical activity in a sample of sixth- and eighth-grade girls. The measure was developed as part of the Trial of Activity for Adolescent Girls (TAAG), a multicenter intervention study to promote PA in middle school girls. The candidate items for the school climate measure were developed through a review of qualitative research with adolescent girls including formative assessment conducted as part of the developmental phase of TAAG, as well as resources designed for school-level assessments, such as the CDC’s School Health Index21 and the National Association of School Physical Educators’ PE Program Improvement and Self-Study Guide for middle schools.26 After developing the scale items, we used standard confirmatory factor analytic procedures27,28 to establish the factorial validity and the multigroup and longitudinal factorial invariance of the school climate measure in samples of sixth- and eighth-grade girls. After the factorial validity and invariance of the measure were established, structural equation modeling was used to assess construct validity of the school climate measure by testing its relationship with physical activity, as well as the equivalence of that relationship between the 2 groups of girls (sixth and eighth graders), using standard procedures.29