Systematic Review Methods: The Science of Research Synthesis

The strongest empirical evidence for social change comes not from single studies but from scientific analyses and syntheses of multiple studies on the same topic. Replication is an essential principle of science, but pure replications are very rare in social work research. Instead, most studies investigate variations on important themes: How widespread are various conditions? Which risk and protective factors are associated with specific conditions? How acceptable are certain interventions in different populations? Which interventions have been rigorously evaluated with what results? What works best for whom under what conditions? These questions and others can be addressed with systematic reviews and meta-analyses, even in the presence of substantial (and statistical) heterogeneity across studies.