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A population-based analysis of the discrepancy between potential and realized access to trauma center care
David Gomez1, Barbara Haas, Aristithes G Doumouras
1Keenan Research Centre in the Li Ka Shing Knowledge Institute of St Michael's Hospital, University of Toronto, Ontario, Canada. Gomezjaramid@smh.ca
Objective:
To explore whether a discrepancy between the availability of trauma services (potential access) and trauma center utilization rates (realized access) exists, with the aim of informing strategies to improve access.
Background:
Lack of access to trauma center care has frequently been attributed to the geographic distribution of trauma centers. Alternatively, impeded access to trauma center care might be due to suboptimal triage practices in the setting of appropriate resources.
Methods:
Population-based retrospective cohort study of severely injured adult patients (2002-2010). Potential access to trauma center care was evaluated using network-based spatial analysis of census data and was defined as residing within 1 hour of a trauma center. Realized access to trauma center care was evaluated using population-based data sources and was defined as direct transport from the scene of injury to a trauma center. Concordance between potential and realized access (high, moderate, or low) was evaluated at the county level.
Results:
Of the population in the study region, 7,340,711 persons (60%) had potential access to trauma center care; persons in 11 counties (22%) had high potential access. Of 26,861 severely injured patients, 10,237 (38%) had realized access to trauma center care; patients in only 4 counties (8%) had high realized access. The concordance between potential and realized access was moderate (weighted κ = 0.49); 63% of counties (n = 7) with high potential access performed worse than expected and had moderate or low realized access.
Conclusions:
There is limited concordance between potential and realized access. Regions with high potential access had low realized access, and vice versa. This evaluation suggests that strategies to improve access must be based on understanding the distribution of centers and the triage practices used to access trauma care.
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