A prospective health impact assessment of the Merseyside Integrated Transport Strategy (MerITS).

BACKGROUND Prospective health impact assessment is a new approach to predicting potential health impacts of policies, programmes or projects. It has been widely recognized that public policies have important impacts on health. In 1997, the Liverpool Public Health Observatory was commissioned to carry out a health impact assessment of the Merseyside Integrated Transport Strategy (MerITS). A secondary aim was to pilot a method for health impact assessment at the strategic level. METHODS The methods used drew on previous health impact assessments of projects, on strategic environmental assessment, and on policy research. They included policy analysis, semi-structured interviews with key informants and literature searches. RESULTS Four priority impact areas of MerITS were identified: establishing road hierarchies, economic viability, air quality, and public transport. Potential health impacts in each of these areas were estimated, and recommendations were made to minimize the effects of negative impacts and to enhance positive ones. CONCLUSION This health impact assessment prospectively identified the key health impacts of a strategy on a defined population and made recommendations to maximize potential positive and minimize potential negative health impacts. The methods employed are generally applicable to prospective health impact assessments of public policies and strategies.