Creating and Using Index Scores in the Analysis of School Policy Implementation and Impact

BACKGROUND: Epidemic increases in childhood obesity and associated health risks are resulting in efforts to implement school policies related to nutrition and physical activity (NPA). With multicomponent policy efforts, challenges exist in characterizing the extent of policy change across the breadth of NPA policies. METHODS: Aggregated policy indices were created to characterize NPA policy implementation in Arkansas public schools from 2004 through 2009. Index scores are presented by year, domain, and school level. RESULTS: Both mean and median index scores increased over time, with greater changes seen in nutrition than in physical activity policy scores. The composite index score was heavily dependent on the nutrition index score and, thus, is relatively less useful for the purposes of our evaluation. Policy index scores varied by school level, rurality, enrollment size, and percentage of students eligible for federal meal programs. CONCLUSIONS: The policy index approach facilitates the consideration of the effect of school policy change in a holistic, aggregated way. School characteristics influence policy adoption, and thus, should be taken into consideration in the promotion of policy change.