Organisation of evidence-based knowledge production: evidence hierarchies and evidence typologies

The evidence movement and the idea of systematically synthesising results from primary studies has gained support in recent years. As the movement has moved into still more policy fields, from medical treatment to, for example, public health, social welfare, and education, review practice has also been developed. The initial evidence hierarchy based standard given priority to randomised controlled trials and meta-analysis advocated by the Cochrane and Campbell collaborations has become supplemented with evidence typologies and review practice paradigms stressing the importance of contextual factors as explanations of differences in effects. In addition to analysing and discussing this development, the article discusses the organisation of dissemination of evidence. This topic is interesting because it is part of the self-perception of the evidence movement that evidence should be brought to use in both practice and policy making.