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Health Impact Assessment

  	children riding bikes Doctors advise their patients on how they can stay healthy. In many ways, Health Impact Assessment (HIA) provides the same advice to communities. This advice helps communities make informed choices about improving public health through community design.

CDC’s Healthy Community Design Initiative is the only source of federal expertise to help states and communities integrate health considerations into transportation and community planning decisions. Learn more about how the Healthy Community Design Initiative supports the use of HIA.

HIA is a process that helps evaluate the potential health effects of a plan, project or policy before it is built or implemented. An HIA can provide recommendations to increase positive health outcomes and minimize adverse health outcomes. HIA brings potential public health impacts and considerations to the decision-making process for plans, projects, and policies that fall outside the traditional public health arenas, such as transportation and land use.

The National Research Council defines HIA as “a systematic process that uses an array of data sources and analytic methods, and considers input from stakeholders to determine the potential effects of a proposed policy, plan, program, or project on the health of a population and the distribution of those effects within the population. HIA provides recommendations on monitoring and managing those effects.”

The major steps in conducting an HIA include

  • Screening (identifying plans, projects or policies for which an HIA would be useful),
  • Scoping (identifying which health effects to consider),
  • Assessing risks and benefits (identifying which people may be affected and how they may be affected),
  • Developing recommendations (suggesting changes to proposals to promote positive health effects or to minimize adverse health effects),
  • Reporting (presenting the results to decision-makers), and
  • Monitoring and evaluating (determining the effect of the HIA on the decision).

The U.S. Department of Health and Human Services recommends HIA as a planning resource for implementing Healthy People 2020. HIA supports two key directions of the Office of the Surgeon General’s National Prevention Strategy: Building Healthy and Safe Community Environments and Empowering People to Make Healthy Choices [PDF - 4.67 MB]. The CDC Recommendations for Improving Health through Transportation states that HIA may be a useful tool for identifying the impact of a new policy, program, or major transportation project on community and individual health. The 2011 CDC co-sponsored National Research Council report Improving Health in the United States: The Role of Health Impact Assessment found that the HIA holds promise for incorporating aspects of health into decision-making because of its

  • Applicability to a broad array of policies, programs, plans, and projects;
  • Consideration of adverse and beneficial health effects;
  • Ability to consider and incorporate various types of evidence; and
  • Engagement of communities and stakeholders in a deliberative process.

HIA is different from a public health assessment, a health risk assessment, and an environmental impact assessment. The differences are explained here. HIA is usually voluntary, though several local and state laws support the examination of health impacts in decision-making and a few explicitly require the use of the HIA.

Outside the United States, HIA is more widely used; some countries have mandated HIA as part of a regulatory process. In the United States, HIA is a rapidly emerging practice among local, state, and federal jurisdictions, mostly on a voluntary basis. A list of more than 150 HIAs completed or in progress in the United States is available at

HIA can be a valuable tool for use in a Health in All Policies approach to decision-making. Examples can be found in the California Executive Order on Health in All Policies and Collins J, Koplan JP. Health impact assessment: a step toward health in all policies [PDF - 126 KB] JAMA. 2009; 302(3):315–317.

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CDC’s Healthy Community Design Initiative and HIA

CDC’s Healthy Community Design Initiative is the only source of federal expertise to help states and communities integrate health considerations into transportation and community planning decisions. The Healthy Community Design Initiative supports the use of HIA by:

  • From 2006 to 2012, funded and provided technical assistance for 34 completed HIAs. Many of these communities have voluntarily chosen to continue HIA activities after direct CDC support ended.
  • Funding six local, county and state health and planning departments in 2011 to conduct at least three HIAs a year for the next three years, and provide training and technical assistance on how proposed projects, policies, and state, tribal and local decisions can affect community health.
  • Funding an online course, developed by the American Planning Association and the National Association of County & City Health Officials, that explains the value of conducting an HIA and the steps involved in conducting an HIA. The site went live in 2009, and as of 2012, more than 5,000 health and planning professionals have taken the course.
  • Developing tools for local health and planning professionals, including a transportation HIA toolkit.
  • Equipping health departments to build ongoing relationships with non-health sectors such as local governments or planning commissions to help communities build infrastructure that maximizes health overall.
  • Providing scientific expertise to promote important federal priorities like the National Prevention Strategy’s focus on healthy physical environments.

The Different Types of Health Assessments

What is the relationship of HIA to Environmental Impact Assessment?

Health Impact Assessment Resources

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