Injury severity measures are becoming increasingly important for quality assurance and injury research. TRISS analysis, which uses the Revised Trauma Score (RTS) and Injury Severity Score (ISS) to predict survival, is an effective tool for comparing outcomes between trauma centers. It has been argued that blunt trauma outcome differs between children and adults, yet the Major Trauma Outcome Study (MTOS) adult data base (ages 15-54 years) regression weights have been used by others to calculate TRISS scores for injured children. This study appears to be the first to perform TRISS analysis on groups of children and adults treated by the same surgeons using the same treatment protocols to assess the validity of applying "adult" TRISS analysis to children. The charts of 346 consecutive children (ages 0-14) and 346 random adults (ages 15-54) admitted to a regional trauma center for isolated blunt trauma over a 30-month period were reviewed for demographics, mechanism of injury, RTS, ISS, and survival. Statistical evaluation included TRISS survival analysis and calculation of the Z statistic. The median ISS was 10 for both children and adults. The Z statistics for children and adults were similar (1.85 and 1.81). Analysis demonstrated the groups to be statistically identical with a nonsignificant trend toward improved survival compared with the MTOS baseline group. These data support the use of existing TRISS analysis for evaluation of pediatric trauma care.