Geographic variation in outcomes from severe traumatic brain injury

Recent reports have documented a wide range of outcomes after treatment of severe traumatic brain injury at trauma centers throughout the world.

In an effort to test the contribution of geography to treatment outcome, we compared case series published from 1975 to 2009. Trauma centers were divided into those from the United States, other developed countries, and the developing world. We pooled data on mortality rates using meta-analytic techniques, and corrected for temporal trends and other covariates using meta-regression.

Our search yielded 231 case series, totaling more than 121,000 cases. There was a decrease in mortality over time in all three geographic locales. The small advantage the United States had versus other high and moderate income countries tended to decrease over time, whereas low income countries reported significantly greater mortality, and their rates decreased more slowly over time.

Low income countries have the highest mortality rates in treating patients with severe closed traumatic brain injury. The lower intensity of treatment appears to be the largest contributor to the discrepancy, and other possible causes are discussed.