Evidence to action in the developing world: what evidence is needed?

Can it work? Will it work? Is it worth it? These three questions constantly face health policy-makers, for whom access to the most relevant and useful evidence is critical.

However, evidence in the clinical care context differs from evidence in the public health and health policy domains. It is often difficult to apply rigid hierarchies of evidence to public health policy. Although randomized controlled trials and systematic reviews are methods of choice when assessing the effectiveness of medications, complex health-care problems pose different challenges.^1–3

Evidence providers and health policy-makers from developing countries have insisted that evidence needs to be broader than that based solely on randomized controlled trials. Observational studies, qualitative research and even “experience”, “know-how”, consensus and “local knowledge” should also be taken into account.

For example, Indonesia tapped into village wisdom to formulate actions and policies to combat avian influenza.⁴ Locally-generated evidence reformed social health insurance in Mexico⁵ and Thailand; it also improved primary health care in the United Republic of Tanzania⁶ and mental health-care policy in Viet Nam.⁷ In these five examples, findings were interpreted and utilized against a background of global evidence and experience from different settings.

In terms of generating the evidence, policy-makers should be involved from the start in defining the specific policy question and processes for developing the evidence base and interpreting reviews and evidence summaries. Research provides only one type of evidence, and policy decisions are invariably made within the context of other social, political, cultural and economic factors.² Different policy questions may require different types of evidence.

Arguably, evidence for policy and action in a public health context also requires innovation beyond the health sector. As an example, policies for vaccination strategies in humans can be combined with those for animals to achieve synergies and efficiencies in resource-poor settings.⁸

Timeliness is another important issue. The reality is that policy-makers are under pressure to implement policies rapidly, often in the absence of relevant evidence on the likely outcomes of their decisions. What is WHO doing to ensure that national research agendas are designed to address this lack of evidence?

Through EVIPNet (Evidence-informed Policy Networks),⁹ WHO is working to build capacity in countries for linking the producers and users of knowledge. The Alliance for Health Policy and Systems Research and WHO are promoting more health systems research, including context-specific research that is often most needed for national decision-making.¹⁰

Evidence-based public health is an exciting and emerging field. However, it is still in its infancy, is comparatively imprecise and definitely needs more support for its further development. It bravely tries to merge the “science” with the “art” of health policy-making, and takes into account the reality that “scientific findings do not fall on blank minds that get made up as a result. Science engages with busy minds that have strong views about how things are and ought to be ...”¹¹ A realistic view of evidence in health policy-making will serve to move the field forward for the benefit of all. ■