Health impact assessment

An idea whose time has come

The Health of the Nation, England's strategy for a healthy population, acknowledges explicitly that many government policies have an impact on health and that their consequences for health need to be assessed and, when appropriate, taken into account.1 England is not alone: the idea of health impact assessment is almost universally popular, though its implementation is patchy. In the developing world, where the importance of healthy public policy is well understood, the prospective assessment of the health impact of resource allocation policies or of development projects is nothing new.2 3 In the developed world, however, acknowledgement of the need for health impact assessment is still in its early stages, and its meaning, methods, and application remain to be established. Only now is the scientific community coming to realise the crucial role of public and private policies and projects in influencing the public's health.

The Commission of the European Union has recently stated that article 129 of the European Union Treaty “requires the Commission to check that proposals for policies, and implementing measures and instruments, do not have an adverse impact on health, or create conditions which undermine the promotion of health.”4 Such an acknowledgement is well overdue, given the European Union's current policies of funding the promotion of whole fat dairy produce and tobacco production.5

In the United Kingdom the need for health impact assessment as an integral feature of policy development and evaluation is no less pressing. There are many examples of adverse effects on health that a prospective assessment of the health impact of public policy could help avoid. These include the increased incidence of myocardial infarction that results from work environments which place high psychological demands on workers but allow them little scope for decision making and control of those demands6; the motor vehicle accidents associated with transport policies that put freedom of traffic flow above the safety needs of communities7; and the increased poverty and exposure to cold caused by the imposition of value added tax on fuel.8

In this context the recent publication of a British government booklet on policy appraisal and health9 is welcome—as is its distribution to local authorities as well as to the health sector in England. But its exclusive focus on economic appraisal methods of health impact assessment puts at risk its otherwise laudable objectives.

Impact assessment for outcomes other than health has become established in the developed world in recent decades, most notably as a result of the United States' National Environmental Policy Act of 1969. This act was rapidly followed by the development and implementation of methods for environmental (and later for social) impact assessment,10 focusing chiefly on the identification, assessment, and management of risk.11 Methods for assessing the impact of policy (as distinct from policy evaluation, which examines the extent to which a policy meets its stated objectives) are still in the formative stages.12 13 14 15

Emerging methods for health impact assessment are likely to draw heavily on the experience of practitioners in these closely related fields. The methods all emphasise the importance of focusing on equitable outcomes; explicitly targeting disadvantaged groups; enabling the full participation of those likely to be affected by the policy or project; and using qualitative as well as quantitative methods of inquiry. The economic contribution is but one important element within a multidisciplinary framework broad enough to encompass the wide range of impacts on health. The need for a broad framework, and not simply one that concentrates on economic methods and outcomes, was confirmed in the United Kingdom's sole example of a completed prospective health impact assessment, which assessed the potential health impact of an additional runway at Manchester Airport (K Ardern, personal communication). While the government's initiative represents a welcome foot in this particular door, much still remains to be done before evidence based policy making can become a reality.16