Evidence-based purchasing of health promotion: methodology for reviewing evidence

In recent years, greater emphasis has been placed on evidence-based practice by health care purchasers, managers and practitioners around the world. This is seen as a means of delivering greater benefits to patients and populations within existing resources. Evidence-based practice requires accessible information in a form that is relevant to the problems decision-makers face. The process of evidence-based practice needs to be informed by the best available research evidence of the effectiveness of healthpromoting interventions combined with good judgement as to the applicability of that evidence and the feasibility of implementation in the local context. The nature of evidence which can be brought to bear on the decision-making process may vary in both quality and reliability. In the field of health promotion, the nature of problems requiring solutions is complex. Commonly there are multiple variables affecting multiple health outcomes. In addition, there is limited available evidence for the effectiveness of interventions and it is of variable quality. These factors pose problems for ensuring evidence-based health promotion. This article describes New Zealand research commissioned by one of four regional purchasers of health services. The purchaser required the development of a framework to prioritize interventions in 22 health promotion areas identified as priorities by the Minister of Health. Our framework was used to consider a broad range of different kinds of evidence, including scientific research, organizational capacity, socio-cultural factors and local community-based knowledge related to the determinants of health. Making explicit the nature of our framework and the evidence we considered, enabled our recommendations about the most appropriate interventions to be as valid and reliable as possible. Our judgement is that as for evidence-based medicine, evidence-based health promotion must employ both quantitative and qualitative evidence, and that the final judgement about purchasing of health promotion initiatives is essentially subjective and political. Evidence-based purchasing of health promotion: methodology for reviewing evidence