- Relevance/health impact: The societal burden of TBI is immense. While the potential for dramatically reducing morbidity and mortality by early treatment appears to be great, the effectiveness of the prehospital guidelines remains unproven. Demonstrating the impact of guideline therapy would potentially lead to widespread implementation of the effective interventions. This could dramatically reduce morbidity and mortality from this major public health problem. On the other hand, if the guidelines are not effective despite confirmed implementation across a wide variety of EMS systems throughout the entire state, this would provide the ethical basis for conducting future randomized trials.