Study Sounds Death Knell for TRISS
Major Finding: Overall mortality rates have doubled since the late 1980s, antiquating the Trauma-Related Injury Severity Score (TRISS), which was based on earlier outcomes data.
Data Source: An analysis of three trauma databases.
Disclosures: Dr. Rogers, his coauthors, and Dr. Nathens reported no financial conflicts of interest.
FROM THE ANNUAL MEETING OF THE EASTERN ASSOCIATION FOR THE SURGERY OF TRAUMA
Dr. Rogers called for a prediction model with a fundamentally sound statistical underpinning that would minimize missing variables such as Glasgow Coma Scale scores, maintain accuracy over time, and contain a clear mechanism for periodic updating.
During the discussion of the study, Dr. Rogers said they compared mortality across ISS categories in the NTDB and PCOS databases and that their comparison confirmed the PTOS finding that mortality has declined over time, after controlling for both ISS and age, in blunt trauma and less convincingly for penetrating trauma.
He suggested that outcomes may have improved in blunt trauma patients because CT scanning has allowed more accurate probing of injuries and that improved field care may be allowing more penetrating trauma patients to survive long enough to get into the data set, but not necessarily out of the hospital.
Finally, TRISS founder and former EAST president Dr. Howard Champion rose from the audience to congratulate the authors on the study and for pointing out the "obvious frailties of TRISS." He suggested the issue revolves around three problematic elements: taxonomy coding, the model, and the coefficients attached to the model.
He pointed out that the United States uses the ICD-9 code, while the rest of the world uses the ICD-10 code and the ICD-11 code is on the horizon. "In other words, we are about two generations behind."
He went on to say that the Abbreviated Injury Score, which is integral to the ISS, was developed in the 1960s and 1970s for engineers and had 78 codes. That number has mushroomed to more than 2,000, and up to 80% of those codes are not used. "There are huge inter-reliability problems with it, suggesting that the Abbreviated Injury Score needs another careful look, as well as the models and the coefficients."
He closed by saying, "There’s a lot to be done. It is not a simple problem; it’s a very challenging problem."
Dr. Rogers said progress will be made by identifying better, more robust predictors for use in trauma outcome models.
Dr. Rogers, his coauthors, and Dr. Nathens reported no conflicts of interest.
