Identifying a 'super-responder' phenomenon in three African countries: Implications for prehospital emergency care training.

BACKGROUND: Few countries in Sub-Saharan Africa have robust emergency medical services (EMS). The WHO recommends training lay first responders (LFRs) as the first step toward EMS development while Disease Control Priorities (DCP) suggests training 0.5%-1% of a population for adequate emergency catchment. After launching three LFR programs in Africa, this study investigated subsequent skill usage and conducted demographic analyses to inform future recruitment of high-responding LFRs. METHODS: Demographic characteristics and individual LFR intervention frequencies were collected from a pooled sample of 887 of 1,291 total LFRs (68.7%) trained across programs launched in a staggered fashion between 2016-2019 in Uganda, Chad, and Sierra Leone. A Kruskal-Wallis Rank-Sum test assessed between-group differences among demographics in each location. Spearman's r was used to determine the relationship between response frequency and LFR characteristics. RESULTS: Most LFRs trained did not use skills post-training (median LFR interventions=0.0 interventions/year [IQR:0.0,5.0]). Right-skewed intervention frequency distributions demonstrate high-responding outlier responder groups do exist in all locations (p<0.0001). Median LFR interventions of the top quartile of these active LFRs ("super-responders") was 26.0 interventions/year (IQR:16.7,35.0). "Super-responders" witnessed more road traffic injuries (RTIs) prior to training (p=0.033). LFRs who never responded were significantly younger (p=0.0020). Significant correlations were demonstrated between pooled RTIs witnessed and intervention frequency (r=0.13, p=0.032) and age and intervention frequency in Sierra Leone (r=-0.15, p=0.019). CONCLUSION: Current DCP-recommended training of 0.5-1% of a given population for adequate emergency catchment may be an inefficient means of building emergency care capacity. Recruiting "super-responders" with select characteristics may achieve similar coverage while conserving valuable training resources in resource-limited African settings.