Time and place of death from automobile crashes: Research endpoint implications.

BACKGROUND: Vehicle crashes are a leading cause of US injury and death. Early death, however, has almost entirely been studied in-hospital. The US Department of Transportation Fatality Analysis Reporting System (FARS) database captures both prehospital and in-hospital mortality. METHODS: FARS location (prehospital, in-hospital) and time of death were reviewed (1978-2013), and a 2003-2005 subgroup of 55,537 early deaths (i.e., between 5 minutes and 4 hours after injury) was analyzed to quantify risk of death over time. RESULTS: There has been an overall decrease in 1978-2013 US vehicle-related deaths (from 3.3 deaths per 100 million vehicle miles traveled to 1.1 and from 22.6 per 100,000 population to 10.4). Snapshots of the death data reveal an overall downward trend of total in-hospital and prehospital deaths. The proportion of hospital deaths decreased by 58%, whereas the proportion of deaths in the prehospital period increased to 56%. Subgroup analysis revealed a rate of mortality risk of 0.4% per minute for the first 30 minutes, 1% per minute for the next 60 minutes, and 0.2% per minute and plateauing thereafter. CONCLUSIONS: Analysis of census FARS data of motor vehicle crash-related deaths showed an overall 35% decrease in mortality over a period of 36 years. The disproportionate reduction in in-hospital deaths is perhaps a testament to the effectiveness of trauma centers. However, there is a demonstrable need to focus on prehospital deaths with resuscitative and adjuvant therapy research and trauma system design. Quantifying risk of death over time should help focus emergency medical services, trauma system, and resuscitation goals. LEVEL OF EVIDENCE: Epidemiologic study, level III.

Combat injury coding: a review and reconfiguration.

BACKGROUND: The current civilian Abbreviated Injury Scale (AIS), designed for automobile crash injuries, yields important information about civilian injuries. It has been recognized for some time, however, that both the AIS and AIS-based scores such as the Injury Severity Score (ISS) are inadequate for describing penetrating injuries, especially those sustained in combat. Existing injury coding systems do not adequately describe (they actually exclude) combat injuries such as the devastating multi-mechanistic injuries resulting from attacks with improvised explosive devices (IEDs). METHODS: After quantifying the inapplicability of current coding systems, the Military Combat Injury Scale (MCIS), which includes injury descriptors that accurately characterize combat anatomic injury, and the Military Functional Incapacity Scale (MFIS), which indicates immediate tactical functional impairment, were developed by a large tri-service military and civilian group of combat trauma subject-matter experts. Assignment of MCIS severity levels was based on urgency, level of care needed, and risk of death from each individual injury. The MFIS was developed based on the casualty's ability to shoot, move, and communicate, and comprises four levels ranging from "Able to continue mission" to "Lost to military." Separate functional impairments were identified for injuries aboard ship. Preliminary evaluation of MCIS discrimination, calibration, and casualty disposition was performed on 992 combat-injured patients using two modeling processes. RESULTS: Based on combat casualty data, the MCIS is a new, simpler, comprehensive severity scale with 269 codes (vs. 1999 in AIS) that specifically characterize and distinguish the many unique injuries encountered in combat. The MCIS integrates with the MFIS, which associates immediate combat functional impairment with minor and moderate-severity injuries. Predictive validation on combat datasets shows improved performance over AIS-based tools in addition to improved face, construct, and content validity and coding inter-rater reliability. Thus, the MCIS has greater relevance, accuracy, and precision for many military-specific applications. CONCLUSION: Over a period of several years, the Military Combat Injury Scale and Military Functional Incapacity Scale were developed, tested and validated by teams of civilian and tri-service military expertise. MCIS shows significant promise in documenting the nature, severity and complexity of modern combat injury.