Recent advances in meta-analytic techniques provide a useful framework for interpreting the findings of individual studies. Simple formula are presented for determining whether the results of a single study are statistically different from the cumulative average of previous studies, and for calculating the new cumulative average. When applied to two controversial social policies (treatment of sexual offenders ; rape prevention programs for college women), cumulative meta-analyses suggested patterns that were not identified by the authors of the individual studies nor by narrative reviews of these content areas.
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