Improving the sensitivity and specificity of the abbreviated injury scale coding system.

The Abbreviated Injury Scale with Epidemiologic Modifications (AIS 85-EM) was developed to make it possible to code information about anatomic injury types and locations that, although generally available from medical records, is not codable under the standard Abbreviated Injury Scale, published by the American Association for Automotive Medicine in 1985 (AIS 85). In a population-based sample of 3,223 motor vehicle trauma cases, 68 percent of the patients had one or more injuries that were coded to the AIS 85 body region nonspecific category external. When the same patients' injuries were coded using the AIS 85-EM coding procedure, only 15 percent of the patients had injuries that could not be coded to a specific body region. With AIS 85-EM, the proportion of codable head injury cases increased from 16 percent to 37 percent, thereby improving the potential for identifying cases with head and threshold brain injury. The data suggest that body region coding of all injuries is necessary to draw valid and reliable conclusions about changes in injury patterns and their sequelae. The increased specificity of body region coding improves assessments of the efficacy of injury intervention strategies and countermeasure programs using epidemiologic methodology.