Injury scaling as a means for classifying the extent of trauma has a long histroy. This paper describes the oriin, development and usage of the Abbreviated Injury Scale. Major revisions to AISJO are discussed in detail. Both the value of the AIS as a research tool and its limitations are presented. The critical need for training AIS users in proper application is addressed. The future role of the Committee on Injury Scaling is explained, and three potential uses of the AIS are suggested as priority items. The paper, accompanied by a comprehensive bibliography, serves as a basic state of the art reference for physicians and others researchers in the traffic medicine and highway safety field.
Injury scaling, or the assessment of the severity of trauma-related tissue damage, dates back many years. Not until around the mid-2Oih century, however, when the enormous toll from motor vehicle related morbidity and mortality was emphasized did it become obvious that better methods for studying injuries were necessary. Considerable progress has been made since the development of the first widely recognized injury scale designed by DeHaven and his associates to study light plane crashes at the then Crash Injury Research Project at Cornell University Medical College in 1943 [Braunstein, 19571. Shortly thereafter, it became apparent that this early DeHaven scale was adaptable to motor vehicle injury research as well.
EARLY CLASSIFICATION SYSTEMS
Between 1943 and 1945, many systems were developed to categorize injuries, but most had serious shortcomings from the medical standpoint as far as assessing motor vehicle related injury severity. The International Classification of Diseases [ 1%7] comprised of a 3 or 4 digit code to specify the nature and site of bodily injury is useful to develop incidence data. However, it cannot readily compare an injury and its severity since its primary purpose is simply to identify diseases and injuries by code numbers.
A scale developed by the National Safety Council uses the descriptions of fatal, serious, minor, and non-visible to identify injuries. The Manual of Classification of Motor Vehicle Trufic Accidents [1%2] has served to provide mass data, but is seriously limited as a research tool to assess injury severity and location.
Two similar scales designed to assess the patient's overall condition were used in the Arizona Air Medical Evaluation System[Williams and Schamadan, 1%9] and at Yale University[Keggi, 1%9]. Neither, however, were adequate for rating injury severity. A DeHaven-type scale developed at Cornell University specifically for motor vehicle related injuries provided a simple but effective means for identifying injuries [Ryan and Garrett, 19681. The terms moderate, severe, serious, critical and fatal along with corresponding code numbers, did offer a system for rating injuries, but still was regarded as inadequate. A number of other scales [Nahum, 1%9; States, 19691 were akin to the one used at Cornell. Injury scaling techniques were not unique to the United States, in that researchers in Great Britain devised similar methods [Mackay, 1%9], as did the Canadians [Campbell, 19691.
MEDICAL PROFESSION INVOLVEMENT
The embryonic stages of injury scaling within organized medicine were initiated in I%6 through the American Medical Association and its Committee on the Medical Aspects of Automotive Safety. After several years of investigatory groundwork, including a thorough review of existing scaling and classification systems, a group of physicians, researchers and