TraumAID is a computer-based decision aid that uses decision rules and logical deduction to generate management plans for the initial definitive management of injured patients; its use is currently confined to assessing penetrating thoracoabdominal injuries in nonpregnant adults. These management plans were compared to trauma center care in an American urban medical school hospital. The TraumAID program was available to trauma chief residents for patient care during the "golden hour." Resulting changes in plans were documented by the residents, For 15 months the management plans for all applicable patients were documented serially., as were computer plans and outcomes. The sequential care and computer-generated care plans were then blinded and judged by three other trauma surgeons as to acceptability, and preference. A consecutive series of 97 patients was evaluated. The residents used the computer for 40 cases during patient care. In 5 of the 40 cases, they altered their evaluation, diagnosis, or treatment: in none of these 5 was the alteration judged an error. Of the 97 patients, 10 had adverse (outcomes, 2 of which were judged potentially avoidable. with unacceptable errors in management. TraumAID's plans were acceptable for both. In 31 cases previously managed by the judges themselves, the TraumAID plans,Acre preferred by the judge to the care he or she had provided, by a ratio of 25:6 (p < 0.61). In a preliminary assessment, computer-generated, patient-specific protocols for the acute management of injuries were preferred to actual care previously given by the judges themselves and were associated with improved care and potential improvement in outcome.