Evidence-based policy making in health care: what it is and what it isn't.

In this paper, I aim to re-establish the meaning and importance of the concept of 'evidence-based policy making' (EBP) in health care. The term EBP is often misunderstood as being either vacuous (who thinks that public policy should not be based on evidence?), unrealistic (the naive product of ivory tower thinking) or conservative (an excuse permanently to delay reform). It need be none of these things. EBP should be thought of as a set of rules and institutional arrangements designed to encourage transparent and balanced use of evidence in public policy making. As well as controlled trials and observational studies, a broad range of theoretical and empirical evidence about human behaviour may be relevant to predicting policy outcomes - including stakeholder opinions and other sources of intelligence that might not qualify as scientific research. Gradual progress towards EBP, properly understood, has the potential to facilitate open democracy and to improve policy outcomes. The argument is illustrated using examples based on large-scale policies of health care reform in England, where progress towards EBP over the last decade has been real but modest.