Abstract

It is probably not surprising, but when most people talk about the ?getting and using? of evidence in health care, they are usually referring to evidence about treatments - things like pills and procedures. Despite this contemporary focus on health treatments, there is a long history of evaluating social, as well as clinical, interventions. Methods developed to answer evaluation questions of social interventions arose early in the twentieth century, and were applied, for example, to evaluate large-scale social programs in the USA (Oakley, 2001, pp.17-19). The study design of meta-analysis, used to synthesise the evidence from a number of studies of similar interventions, has been picked up and developed within medicine as well (Daly, Kellehear, & Gliksman, 1997, pp.139-53). This has led to the establishment of large-scale enterprises such as the Cochrane Collaboration, an example of an international organisation that is assembling and reviewing the effectiveness of many clinical interventions (Chalmers, 1993; Cochrane Collaboration, 2003).