Читать книгу Experimental Evaluation Design for Program Improvement - Laura R. Peck - Страница 16

The fourth set of evaluation research relevant to experiments involves meta-analysis, including tiered-evidence reviews. Meta-analysis involves quantitatively aggregating other evaluation results in order to ascertain, across studies, the extent and magnitude of program impacts observed in the existing literature. These analyses tend to prioritize larger and more rigorous studies, down-weighting results that are based on small samples or that use designs that do not meet criteria for establishing a causal connection between a program and change in outcomes. Indeed, some meta-analyses use only evidence that comes from experimentally designed evaluations. Likewise, evidence reviews—such as those provided by the What Works Clearinghouse (WWC) of the U.S. Department of Education—give their highest rating to evidence that comes from experiments. Because of this, I classify meta-analyses as a type of research that is relevant to experimentally designed evaluations.