Impact assessment is a prospective approach to anticipate future direct and indirect effects of projects, programmes or policies. Through a combination of procedures, tools and methods, systematic impact assessment provides an evidence-base for decision-making on how to adequately manage those effects.
Health impacts are either assessed in a stand-alone health impact assessment (HIA) or integrated in other forms, such as environmental impact assessment (EIA) or environmental, social and health impact assessment (ESHIA).
The holistic HIA approach takes into account direct effects of projects, programmes or policies on human health but equally considers underlying social and environmental determinants of health, which are expected to alter through implementation and indirectly influence population health.
There are several guidance document for HIA available online: