Heat Emergency Awareness and Treatment (HEAT): A Cluster Randomized Trial to Assess the Impact of a Comprehensive Intervention to Mitigate Humanitarian Crisis Due to Extreme Heat in Karachi, Pakistan

This study consists of a community-based and hospital-based components. The community-based study is a prospective two-arm cluster randomized controlled trial and will be implemented in 16 clusters of 1000 people located in the most central neighborhood (called "mohalla") of a Union Council. Minimum required sample size is 7120 in each group, which requires 890 subjects in each of the 16 clusters. Calculations are based on achieving 80% power to detect a difference between the group proportions of 20% from the baseline.

For the hospital component, four major hospitals will be randomized to receive operations and clinical capacity building on management of heat emergencies. The hospital sample size is limited by the availability of hospitals and their uneven distribution which are not linked to union councils in the district.

The primary outcome in the investigators' study is the frequency of emergency admissions to the hospital with all-cause mortality as a secondary outcome.

A community-based and hospital-based protocols and training materials will be developed and will serve as the intervention in this study. These will focus on education about recognizing the signs of symptoms of heat-related illness and proper response and treatment based on local resources.

Data collection will be done at baselines and post-intervention. In the community data on demographics and household characteristics will be collected. Additionally, data on deaths in households will be collected. Changes in knowledge, attitudes, and practices will be measured using a Knowledge, Attitudes, and Practices (KAP) survey pre- and post-intervention.