Development of methodologically acceptable outcomes models for EMS is long overdue. The EMSOP steering committee and consultants propose a conceptual framework that will provide a foundation for future EMS outcomes research using two distinct, conceptual models: 1) The "Episode of Care Model" (see Figures 1 and 2) [Spaite et al., 2001]; and 2) The "Prehospital Unit of Service Model" (see Figure 3) [Spaite et al., 2001].
Model for idetifying the impact of treatment from each "unit of service" in the episode of care
The Episode of Care Model is useful in conditions where interventions and outcomes, especially survival and major physiologic dysfunction, are linked in an extremely time-dependent manner. Non-traumatic cardiac arrest is the prototypical condition for utilizing this model. The Prehospital Unit of Service Model is essentially a sub-unit of the Episode of Care Model. It is valuable for evaluating conditions that have minimal to moderate therapeutic time-dependency. This model should be used when one is most concerned about studying outcomes limited to the prehospital interval. An example of an outcome that could be studied using this model is pain from injuries sustained in a motor vehicle crash. These models should be broadly applied to a wide spectrum of conditions and interventions. We believe that these will be particularly useful in the evaluation of major trauma patients. Further, these models can be applied across the entire spectrum of the "Six Ds" of patient outcomes.