Systematic Reviews & Other Review Types

17 minutes
Joel Gagnier, Associate Professor in the department of Orthopedic Surgery and Epidemiology at the University of Michigan, discusses basic principles and types of systematic reviews, using data extraction tables, effect size, fixed and random effects, and using a forest plot.

Systematic reviews study the findings of research already undertaken. They provide a reliable account of the state of current knowledge (the evidence base) on an issue by appraising and synthesizing the results of "existing research using explicit, accountable rigorous research methods". Systematic reviews developed out of a need to use research findings to help inform policy, practice, and individual decision-making and further research. To use research findings, we need to know what these findings are. What is the current evidence base? What do we know from research and how do we know it? Clarity of what is already known from research is thus the starting point for both using research findings and for planning new research.