Background: Systematic reviews have evolved to address complex issues across health and social policy. Framework synthesis is increasingly employed in systematic reviews to address such complexity. Adapted from framework analysis methods used in primary research, framework synthesis begins with an a priori conceptual framework, which develops iteratively as new data are incorporated and themes are derived from the data. However, framework synthesis appears to have been applied in different ways. 

Objectives: To describe and consider the ways in which framework synthesis is applied and how it is situated in, and contributes to, wider debates about health research synthesis methods. 

Methods: A systematic review was conducted of the literature discussing or employing framework-synthesis methods. Data from included papers were ordered according to an a priori conceptual framework and data synthesised using framework-synthesis methods and constant-comparative analysis.  

Results: We identified 53 papers either discussing or conducting framework synthesis. Earlier reviews synthesised research on people’s experiences of health or healthcare, while newer reviews examined health policy issues. Critical consideration of the transferability, trustworthiness or credibility of findings is inconsistently reported. More recent reviews employing framework synthesis have innovated by: building conceptual frameworks from the views of key stakeholders, including the public; utilising those conceptual frameworks in discussions with review stakeholders; and, in the application of mixed and multiple research methods for synthesis. These innovations can help support stakeholder priorities and ensure that conclusions and recommendations reflect their needs.

Conclusions: Framework synthesis is a flexible research-synthesis method that can meet the complex conditions arising from health policy and healthcare issues. Used increasingly in mixed-method synthesis that emphasises diverse stakeholder consultation, it is a method designed for decision making because it is not framed by academic disciplines or methodologies but by concepts that transcend them.