Methodological Approaches for Measuring the Association Between Heat Exposure and Health Outcomes: A Comprehensive...

Area of Science:

• Environmental Health
• Epidemiology
• Biostatistics

Background:

• Climate change is increasing the frequency and intensity of heat waves globally.
• Understanding the health impacts of heat exposure is crucial for public health planning.
• Methodological heterogeneity in existing research poses challenges for synthesizing findings.

Purpose of the Study:

• To systematically review and synthesize the methodologies employed in studies evaluating the health impacts of heat exposure.
• To identify common analytical approaches and data sources used in heat-health research.
• To highlight variations in methods across different countries and study designs.

Main Methods:

• A comprehensive literature search was conducted across Embase, MEDLINE, Web of Science, and Scopus databases.
• Records were screened for eligibility based on climate-related heat exposure and associated morbidity/mortality outcomes.
• Data abstraction focused on study methodologies, data sources, and analytical techniques.

Main Results:

• 237 articles from 43 countries were analyzed, with most studies originating from China, the USA, and Australia.
• Significant heterogeneity was observed in climate data sources (141 unique), extreme heat thresholds (none standardized), and health outcome data (200 unique).
• Distributed lag non-linear models (DLNM) were most common (48.1%), particularly in time series and ecological studies, while conditional logistic regression was prevalent in case-control and case-crossover designs.

Conclusions:

• The review highlights substantial methodological diversity in heat impact research globally.
• Identified barriers include underrepresentation of certain countries and health outcomes, and limited data accessibility.
• This synthesis serves as a valuable resource for researchers aiming to standardize and advance future heat-health impact assessments.