Objectives: 1. To describe variations in major trauma between rural and urban residents of Ontario in terms of external causes, severities, prehospital care and clinical outcomes. 2. To determine whether prehospital intubation improves survival to hospital discharge among victims of major trauma. Methods: The study involved secondary analyses of data from the Ontario Prehospital Advanced Life Support Study (OPALS). OPALS is the largest study of prehospital emergency medical services conducted worldwide. 1. Rural-urban status of trauma patients was determined using modified Beale Codes. Differences in trauma characteristics and patient care were compared among four geographic groups (Large Metro, Medium Metro, Small Metro, Rural). 2. Patients who were intubated in the field were individually matched with non-intubated patients by patient age, injury severity score category, abbreviated head injury score category, and exact Glasgow coma scores. Cox regression was used to estimate the effect of prehospital intubation on patients' survival to hospital discharge, stratifying on patient matching. Results: 1. Patients in the large metro and rural groups had higher injury severity scores (medial 25, 24, respectively) than the other two groups (median=22). Paramedics generally spent more time in rural and large metro areas (median=37.4, 36.6 minutes respectively) than in medium and small metro (median=32.0, 30.7 minutes respectively) areas. Response times and transport times in rural groups were significantly longer than the other three groups, while scene times in the large metro group were significantly longer compared with the other geographic groups. There were no significant differences in survival rates by geographic group. 2. There were no significantly differences between the intubated and the non-intubated groups by age, sex, Glasgow coma scores, injury severity score, and systolic blood pressure category. Prehospital intubated patients exprienced a 3-fold risk of mortality after adjustment for potential confounders (HR2.9; 95% CI 1.4 to 5.8). Conclusions: 1. While response and transport times for major trauma were longer in rural areas, there were no significant differences in mortality in patients with different rural urban status. 2. Prehosptial intubation showed a negative association with survival among major trauma patients. Further randomized trials are required to invesitigate this clinical issue. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2007-10-24 11:58:53.955