Injury severity scales: overview and directions for future research

The utility of the AIS for classifying trauma patients according to the nature and extent of tissue damage is well documented. The development of the ISS has enhanced the utility of the AIS by making it possible to assess the overall severity of multiple injuries sustained by an individual. Several studies have confirmed the validity of the ISS as a predictor of mortality and length of hospital stay. When the ISS is used in conjunction with a physiological index such as the Trauma Score, its power to predict mortality increases significantly. The inter-rater reliability of the AIS derived from medical records was shown to be substantial for both clinicians as well as nonclinicians. It is important, however, that raters be properly trained and standardized prior to using the scale. Petrucelli et al have developed a training manual for use by crash investigators of the National Highway Traffic Safety Administration of the U.S. Department of Transportation. This manual can easily be adapted for use by those involved in EMS evaluation. With the development of an ICD-9-CM to AIS 80 conversion table, the application of the AIS to large computerized data bases will also become tenable. As more attention is focused on issues of long-term consequences of injury, however, it may become necessary to fine-tune existing scales or construct new ones. As discussed earlier in this paper, there is evidence that the AIS can be used to classify patients according to levels of disability and costs of medical care. The few studies that provide this evidence, however, are limited in scope and generalizability, as they focus on vehicular trauma only. In addition, most of these studies are based on small cross-sectional samples and do not use standardized measurements of functional status. Currently under way as a collaborative study between The Johns Hopkins Medical Institutions and the Maryland Institute for Emergency Medical Services System is a longitudinal study of 600 young adult patients (ages 16-45) who sustained injuries severe enough to require hospitalization. One of the objectives of this study is to test the utility of the AIS/ISS in conjunction with measures of functional status at the time of hospital discharge for predicting changes in physical,mental, and social functioning of trauma patients up to one year following discharge and with direct costs associated with goods and services purchased as a result of the injury.(ABSTRACT TRUNCATED AT 400 WORDS)