AHAH (the index of ‘Access to Healthy Assets and Hazards’) is a multi-dimensional index developed by the CDRC for Great Britain measuring how ‘healthy’ neighbourhoods are. The AHAH index combines indicators under four different domains of accessibility:

• Retail environment (access to fast food outlets, pubs, tobacconists, gambling outlets),
• Health services (access to GPs, hospitals (NHS trust sites), pharmacies, dentists, leisure services),
• Physical environment (Blue Space, Green Space - Passive), and
• Air quality (NO₂, PM10, SO₂).

The dataset available for download contains each input component used to generate the AHAH Index (e.g. ah4dent), which indicates the average drive-time in minutes between each postcode within each LSOA to the nearest health asset. For ah4gpas this value instead presents the mean NDVI value for each postcode within that LSOA, and each air quality component indicates the mean concentration of particals.

For each component, the rank (_rnk) and percentiles (_pct) are normalised so that lower values are better in terms of expected impact on health, while higher values are worse.

Content

Measurement data and deciles for the overall index, 4 domains and 14 inputs are produced for Lower Level Super Output Areas (2021 LSOAs) for England and Wales, and Data Zones (2011 DZs) for Scotland. Distances shown for some of the measurement data are means of the time (in minutes) for driving by car along the established road network, between the population weighted centroid of each postcode contained within each statistical geographical unit, and the actual location of the outlet/service. Please see the Sci Data paper (see Related Content below) for more information - note this paper is about Version 1 of the data.

Version 4 is updated including the most up-to-date data for 2024. AHAH Version 3 (released 2022), Version 2 (released 2017) and Version 1 (released 2016), these can be found on the previous versions page (see links below).

For detailed description of the columns contained within the data, see the Variable Dictionary; and for an overview of the characteristics of the data, see the Data Summary. These files can be downloaded from the bottom of this page.

Quality, Representation and Bias

The data are from multiple data sources. Each were selected following review since they presented the best quality or lowest bias data sources. We checked individual data sources for bias using local checks, however we did not find any issues. All external datasets are validated by their data producer as well.

Data Sources