In this retrospective study, the TRISS method of trauma care analysis is used to compare trauma care at the Hamilton General Hospital (HGH) and the Ottawa Civic Hospital (OCH) with the standards reported in the Major Trauma Outcome Study (MTOS). A total of 274 adult patients with multiple-system injuries were studied; their demographic data, Trauma Scores (TS) on arrival to the Emergency Room, and Injury Severity Scores (ISS) were reviewed. The TRISS scores and Z and M statistics were then calculated. In the Hamilton group, 106 consecutive patients from April through July 1987 were studied. The majority of patients (72%) were male, and the median age was 26 years. The majority of patients (96.2%) sustained blunt trauma, with motor vehicle accidents (MVA) being the most common (76.4%) mechanisms of injury. Fifty-four (51%) of the patients were transferred from outlying hospitals. The Z and M statistics were -0.05 and 0.92, respectively. In the Ottawa group, 168 consecutive patients from April 1987 through October 1988 were studied. The majority of patients (73%) were male, and the median age was 39 years. Blunt trauma accounted for the majority (91.7%) of injuries, with MVAs being responsible for 58% of injuries. Most patients (63.5%) were transferred from regional hospitals. The Z and M statistics were 1.20 and 0.56, respectively. We conclude that the survival statistics of trauma patients treated at both centres are comparable to those of trauma patients in the MTOS.