OBJECTIVE The aim of this study was to identify factors contributing to outcomes after severe traumatic brain injury (TBI) associated with epidural hematoma (EDH). METHODS Between 02/2002 and 4/2010 17 Austrian centers prospectively enrolled 863 patients with moderate and severe TBI into observational studies. Data on accident, treatment, and outcomes were collected. Data sets from patients who had severe TBI (=Glasgow Coma Scale score <9) and EDH were selected. Six-month outcomes were classified as "favorable" if Glasgow Outcome Scale (GOS) scores were 5 or 4, and were classified as "unfavorable" if GOS scores were 3 or less. The Rotterdam score was used to classify computed tomography (CT) findings; the scores published by Hukkelhoven et al. (J Neurotrauma 22:1025-1039, 2005) were used to estimate predicted rates of death and of unfavorable outcomes. Univariate (Fisher's exact test, t test, Chi(2)-test) and multivariate (logistic regression) statistics were used to identify factors associated with hospital mortality and favorable outcome. RESULTS Of the 738 patients with severe TBI 159 (21.5 %) had EDH. Of these, 49 (30.8 %) died in the hospital, 21 (13.2 %) survived with unfavorable outcome, 82 (51.6 %) with favorable outcome; long-term outcome was unknown in 7 survivors (4.4 %). Mortality rates predicted by the Rotterdam score showed good correlation with observed mortality rates. According to the Hukkelhoven scores, observed/predicted ratios for mortality and unfavorable outcome were 0.94 and 0.97, respectively. Age, severity of TBI, and neurological status were the main factors influencing outcomes after severe TBI associated with EDH. We were unable to demonstrate significant effects of treatment factors.