Validity of Trauma and Injury Severity Score Scoring in India.

Sir, Trauma is one of the leading causes of death in India. Prediction of survival following trauma is an important field of research, particularly in India where traditional scoring systems have failed to produce satisfactory results. The origin of the trauma and injury severity score (TRISS) can be traced back to the major trauma outcome study (MTOS) which was conducted in the United States during the 1980s. The TRISS uses the revised trauma score (RTS), injury severity score (ISS), age of the patient, and nature of the injury to predict the mortality of the patient in an emergency trauma care setting. The validity of TRISS scoring has always been put to the test in various countries with diverse patient populations. In the Indian scenario, studies have shown an unsatisfactory correlation of observed patient mortality with the values predicted using the TRISS scoring system. In one such study, the predicted mortality was 10.89% using the TRISS scoring but the observed mortality was found to be 21.26%.[1] The authors concluded that the TRISS scoring, which had its origins in the United States of America, may only be valid for specific conditions in the originating country or countries with similar patient populations. Another Indian study observed mortality of 33.3% as compared to predicted mortality of 15.7% by the TRISS scoring system.[2] The authors concluded that the TRISS methodology with the MTOS coefficients does not accurately predict mortality in developing countries such as India. One of the reasons for the poor correlation of the predicted mortality rates with the observed ones may be the inclusion of ISS. The ISS is a score that requires labor-intensive calculations with specially trained staff, which is unsustainable in low- and middle-income countries.[3,4] The ISS also does not consider multiple severe injuries in the same body region, thereby giving a higher score to a patient with two moderate injuries in two different regions versus someone who has two severe injuries in the same region of the body.[5] The RTS too may not be perfectly accurate since no time adjustment is added to the score since the time of injury. In India, there is no uniform time interval for calculating the RTS after injury. This may introduce bias as fluctuating vital signs and resuscitation efforts tend to normalize physiological parameters giving falsely low predictive mortality rates.[3] Another limitation of the TRISS score would be the fact that often it is a retrospective calculation. This is because an accurate calculation of ISS is usually done retrospectively and is not feasible in the acute setting. Therefore, it is not a viable option to predict probable adverse outcomes on admission.[4] A national trauma registry/database to develop new coefficients suitable in the Indian scenario for predicting adverse patient outcomes in the emergency setting will help to overcome these limitations.[1,2] Research quality and ethics statement The authors followed applicable EQUATOR Network (http://www.equator-network.org/) guidelines, notably the CARE guideline, during the conduct of this report. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.