Identifying the healthy places to live in Australia with a new environmental quality health index

Abstract

Background

Existing environmental quality indices often fail to account for the varying health impacts of different exposures and exclude socio-economic status indicators (SES).

Objectives

To develop and validate a comprehensive Environmental Quality Health Index (EQHI) that integrates multiple environmental exposures and SES to assess mortality risks across Australia.

Methods

We combined all-cause, cardiovascular, and respiratory mortality data (2016–2019) from 2,180 Statistical Areas Level 2 with annual mean values of 12 environmental exposures, including PM_2.5, ozone, temperature, humidity, normalized difference vegetation index, night light, road and building density, and socioeconomic status. Exposure-mortality relationships were estimated using a spatial age-period-cohort model, and EQHIs (scored 0–100, with higher values indicating better conditions) were constructed. Validation was performed using K-fold cross-validation and spatial regression models.

Results

Validation showed strong model performance (R-squared = 83.53 %, 75.55 %, and 52.44 % for EQHI-all cause, EQHI-CVD, and EQHI-Resp). Each interquartile increase in EQHI-all cause reduced all-cause mortality risk by 10 %, with similar reductions for cardiovascular and respiratory mortality. Geographically, EQHIs were higher in south, east, and southeast coastal regions. From 2016 to 2019, SA2s with the highest EQHI (>75) decreased from 27.1 % to 21.1 %. The population weighted EQHI was highest in Hobart and lowest in Darwin.

Conclusions

We established, to our knowledge, the first tool to quantify and communicate environmental health risks using three types of mortality data and 12 environmental factors. This EQHI provides a robust framework to assess environmental health risks and guide targeted interventions. Our methodology can be adapted globally to standardize risk evaluation.