Discrimination (c statistics) and calibration (calibration curves, Akaike's criterion) of hierarchical logistic regression models for hospital mortality comprising TMPM or ISS were compared using trauma-registry data on 3570 patients of years 2007-2009. The completeness of AIS vs. ICD-9-CM coding was also investigated through the ratio of the respective numbers of codes per patient. Model discrimination was further analyzed after stratification according to the above ratio (>1 and ≤ 1).