Time Intervals in Helicopter Emergency Medical Services in Iran: A Systematic Review and Meta-Analysis
Ali Sahebi1, Hamideh Ebrahimi2, Halimeh Kamali3
1Department of Medical Emergencies and Health in Disasters and Emergencies, Ilam University of Medical Sciences, Ilam, Iran.
Air Medical Journal
|May 2, 2026
Summary
Helicopter Emergency Medical Services (HEMS) in Iran show acceptable operational times, averaging 50.59 minutes. Analysis indicates decreasing response and on-scene times but increasing transport times, highlighting areas for improvement.
Area of Science:
- Emergency Medicine
- Public Health
- Healthcare Management
Background:
- Helicopter Emergency Medical Services (HEMS) are vital for rapid emergency care delivery.
- Timely HEMS interventions significantly improve patient outcomes.
- Understanding HEMS time intervals is crucial for optimizing emergency medical response.
Purpose of the Study:
- To systematically analyze Helicopter Emergency Medical Services (HEMS) time intervals in Iran.
- To conduct a meta-analysis of existing studies on Iranian HEMS operational times.
- To identify trends and areas for enhancement in HEMS efficiency within Iran.
Main Methods:
- Systematic review and meta-analysis adhering to PRISMA guidelines.
- Comprehensive database search up to August 2025.
- Inclusion of ten studies with quality assessment and random-effects model meta-analysis using STATA 14.
Main Results:
- Mean HEMS response time: 19.55 minutes.
- Mean on-scene time: 10.46 minutes.
- Mean transport time: 14.63 minutes.
- Overall mean HEMS time: 50.59 minutes.
- Meta-regression showed decreasing response and on-scene times, but increasing transport and overall HEMS times over the years.
Conclusions:
- Iranian HEMS demonstrate generally acceptable operational durations.
- Key areas for enhancement include triage protocols and fleet modernization.
- Establishing a national HEMS registry is recommended for improved evidence-based decision-making and efficiency.
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