Health Impact Assessment

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A Health Impact Assessment (HIA) is a process to evaluate the potential positive and negative public health effects of a plan, project, or policy before it is approved, built, or implemented. State, federal, and tribal governments; community organizations; and other groups are increasingly conducting HIAs to inform decision-making processes for transportation, land use, climate change, and other sectors. Conducting an HIA requires access to high-quality data about many different areas that affect our health including environmental, cultural, economic, and social conditions.

Tracking Data Can Inform HIAs

CDC’s Tracking Network is an excellent data source for environmental hazards, exposures, and health conditions that can be a valuable asset to the HIA process. The Tracking Network provides not only national data but also state and local data. These data may be used in several HIA steps, including community engagement, scoping, assessment, and evaluation.

Types of Data

Data on the National Tracking Network

The National Tracking Network includes data about community design elements, asthma, outdoor air quality, socioeconomic indicators, and more. You can go directly to the data query section of the network to explore these data or visit the data user’s guide and for information about how to use Tracking Network data in an HIA.

Data on State and Local Networks

CDC funds health departments to build and maintain local tracking networks as part of the National Tracking Network. These local networks may include data that are not on CDC’s website. Some of these unique data also may be helpful for conducting HIAs. You can access all state and local networks from this page.

Finding the Data You Need

In addition to providing data through the websites, state and local tracking programs can provide custom data for different levels of geography by request. For example, some tracking programs can provide data for specific ZIP codes or at a community-level. State and city tracking programs can assist with interpretation and visualization of tracking data. For more information, contact CDC’s Tracking Program or explore the state and local networks.

Data Highlight
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Tracking Network Diagrams and Case Studies by HIA

Below are diagrams for three different common HIAs that illustrate how Tracking Network data may be helpful.

Health Impact Assessment Data Guide

This guide provides suggestions for how to use data from the Tracking Network in an HIA. Users who are new to HIA practices are encouraged to seek background information about HIAs here.

Tracking data may be used to inform any of the six steps for conducting an HIA, but this guide focuses on three specific steps:

  • Scoping – to explore health and environment issues of potential interest to a community or when conducting an HIA
  • Assessment – to assess a baseline for conditions, refine priorities, inform communities, or make projections or estimates about trends
  • Monitoring and Evaluation – to evaluate the effects of a decision, policy, or action over time; pre- and post-implementation

Additional Resources

Explore Data
Data Explorer
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Create custom data visualizations, save, & share results

Quick Reports
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View data in simple charts

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Access machine-readable data