Comparisons of the thoracic trauma index with other models

The thoracic trauma index (TTI) provides an indication of the severity of injuries received by motor vehicle occupants in side-impact collision environments. The index was derived from results on two sets of cadaver tests. Using a variety of statistical and numerical methods, the authors reanalyzed the data from these 80+ cadaver tests to construct a better measure of injury than TTI. Indices generated by these analyses were compared with TTI using the following quantitative measures: monotonicity, overlap, percentage correct, and sensitivity. The values of these measures are broadly similar for all indices and none of the new indices consistently performs better than TTI. This suggests that TTI is as good a predictor of injury as any of the several alternative models created.