A systematic approach to conducting a non-statistical meta-analysis of research literature

Liteature analyses and syntheses are bccoming increas-ingly important as a means of periodically beingingcoher' ence to a researcharea area, contributing new knowledge revealed by Lntegrating single studies, and quickly Informing scientists of the state of die fields As. result, there is a need for approaches that can provide replicable, reliable, and trustworthy results. Over the last decade in any researchers have begun using the statistical mera-analysis approach to integrate studies, However, the single studics conducted in many areas are not of the type amenable to statistical meta-analysis but are more appropriate for none-statistical analysis and synthesis. The present paper describes (I) a rigorous approach to conducting a not-statistical meta-analysis of research lit-erature and (2) an example of how this approach was ap- plied to the literature on determinants of primary care Specialty choice published between 1937 and 1993. This approach includes model development, literature retrieval, literature coding, rating references for quality, annotating high-quality references, and synthesizing only the subset of the literature found of sufficient quality to he considered. Also, the basic results of each included study are reported in the synthesis so that readers have before them till the "data points" used in the synthesis. Thus, readers can draw their own interpretations without having to re-collect the data, just as they would he able to do in any single study that presents original data as well as conclusions and discussion.