Research Article| Volume 54, ISSUE 1, P5-14, January 2023

Evaluating feasibility of a novel mobile emergency medical dispatch tool for lay first responder prehospital response coordination in Sierra Leone: A simulation-based study

Published:October 12, 2022DOI:


      • After lay first responder (LFR) training, emergency medical dispatch (EMD) is the next step toward formal emergency medical services (EMS) development in low- and middle-income countries.
      • A novel mobile EMD system was piloted using a mobile phone application with LFRs along 10 kilometers of highway in Sierra Leone.
      • Median total LFR response interval (notification to arrival) to 50 emergency simulations over 3 months was 5 minutes 39 seconds (IQR:0:03:51, 0:09:18).
      • Median first aid skill checklist completion was 89% (IQR: 78%, 90%), suggesting LFRs trained by a 5-hour curriculum and refresher trainings deliver high-quality prehospital care during simulated emergencies.
      • Cost-effectiveness equals $179.02USD per DALY averted per 100,000 people, less than Sierra Leonean GDP per capita, suggesting high cost-effectiveness.



      The global injury burden, driven by road traffic injuries, disproportionately affects low- and middle-income countries, which lack robust emergency medical services (EMS) to address injury. The WHO recommends training lay first responders (LFRs) as the first step toward formal EMS development. Emergency medical dispatch (EMD) systems are the recognized next step but whether small groups of LFRs equipped with mobile dispatch infrastructure can efficiently respond to geographically-dispersed emergencies in a timely fashion and the quality of prehospital care provided is unknown.

      Materials and methods

      We piloted an EMD system utilizing a mobile phone application in Sierra Leone. Ten LFRs were randomly selected from a pool of 61 highly-active LFRs trained in 2019 and recruited to participate in an emergency simulation-based study. Ten simulation scenarios were created matching proportions of injury conditions across 1,850 previous incidents (June-December 2019). Fifty total simulations were launched in randomized order over 3 months, randomized along 10 km of highway in Makeni. Replicating real-world conditions, highly-active LFR participants were blinded to randomized dispatch timing/scenario to assess response time and skill performance under direct observation with a checklist using standardized patient actors. We used novel cost data tracked during EMD pilot implementation to inform the calculation of a new cost-effectiveness ratio ($USD cost per disability-adjusted life year averted (DALY)) for LFR programs equipped with dispatch, following WHO CHOICE guidelines, which state cost-effectiveness ratios less than gross domestic product (GDP) per capita are considered “very cost-effective.”


      Median total response interval (notification to arrival) was 5 min 39 s (IQR:0:03:51, 0:09:18). LFRs initially trained with a 5-hour curriculum and refresher training provide high-quality prehospital care during simulated emergencies. Median first aid skill checklist completion was 89% (IQR: 78%, 90%). Cost-effectiveness equals $179.02USD per DALY averted per 100,000 people, less than Sierra Leonean GDP per capita ($484.52USD).


      LFRs equipped with mobile dispatch demonstrate appropriate response times and effective basic initial management of simulated emergencies. Training smaller cohorts of highly-active LFRs equipped with mobile dispatch appears highly cost-effective and may be a feasible model to facilitate efficient dispatch to expand emergency coverage while conserving valuable training resources in resource-limited settings.


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