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Improvement index
For each outcome domain, the WWC computed an improvement index based on the effect size (see the Technical Details of WWC-Conducted Computations). The improvement index represents the difference between the percentile rank of the average student in the intervention condition versus the percentile rank of the average student in the comparison condition. Unlike the rating of effectiveness, the improvement index is entirely based on the size of the effect, regardless of the statistical significance of the effect, the study design, or the analysis. The improvement index can take on values between -50 and +50, with positive numbers denoting favorable results. The improvement index for behavior is +19 percentile points, with a range of -12 to +36 percentile points. The improvement index for academic achievement is +14 percentile points, with a range of +8 to +36 percentile points.
Summary
The WWC reviewed 12 studies on Positive Action. One study met WWC evidence standards, and one study met standards with reservations. Both studies assessed elementary school student outcomes in the behavior and academic achievement domains. When the WWC aggregated the results in each of these domains, the average effect sizes were statistically significant. So the WWC rated the program as having positive effects on both behavior and academic achievement. Character education, an evolving field, is beginning to establish a research base. The evidence presented in this report is limited and may change as new research emerges.
|Institute of Education Sciences