Related Experiment Video
Updated: May 22, 2026

Problem-Solving Before Instruction (PS-I): A Protocol for Assessment and Intervention in Students with Different Abilities
Published on: September 11, 2021
Creating and using index scores in the analysis of school policy implementation and impact
Martha M Phillips1, Melanie Goodell, James M Raczynski
1Department of Epidemiology, Fay W. Boozman College of Public Health and Department of Psychiatry, College of Medicine, University of Arkansas for Medical Sciences, 4301 W. Markham St. # 820, Little Rock, AR 72205, USA. mmphillips@uams.edu
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.
Related Concept Videos
Review and Preview
Percentiles are a type of fractile that partition data into...
Reliability and Validity
Measures of Intelligence
Validity refers to how well a test measures what it claims to measure. An intelligence test should accurately assess intelligence rather than another characteristic, like anxiety. Criterion validity is one way to evaluate this; it...
Study Design in Statistics
Does aspirin reduce the risk of heart attacks? Is one brand of fertilizer more effective at growing roses than another? Is fatigue as dangerous to a driver as the influence of alcohol? Questions like these are answered using randomized experiments with proper...
Surveys
Strategies for Assessing and Addressing Confounding
Confounding can be addressed at both the design phase of a study and through analytical methods after data...
