An introduction to meta-analysis.

The current rapid pace of social and technological change requires health policy makers to be up to date in their knowledge of health policy research. The "information explosion" has created a need for techniques that synthesize and summarize available information. This paper reviews the use of Meta-Analysis as a data pooling technique in a non-technical manner. Treatment of chronic pain by acupuncture, provided as an example, illustrates the type of information that can be obtained from a Meta-Analysis, that is not conventionally available from individual trials.