Prognostic Accuracy of the Revised Trauma Score, Shock Index, and Injury Severity Score for In-Hospital Mortality in Adult Trauma Patients: A Retrospective Single-Center Cohort Study

Abstract

Background. Early risk stratification is essential in severe trauma, particularly in resource-limited settings. Physiological scores such as the Revised Trauma Score (RTS) and Shock Index (SI) allow rapid bedside triage, whereas the Injury Severity Score (ISS) quantifies anatomical tissue damage.

Objective. To compare the discrimination of RTS, SI, and ISS for in-hospital mortality in severely injured adults.

Methods. This retrospective single-center cohort study included 100 adults aged 20–60 years admitted to the Emergency Department of Dr. Saiful Anwar Regional General Hospital, Malang, Indonesia, in 2023. An outcome-enriched sample (50 survivors, 50 non-survivors) was analyzed. The outcome was all-cause in-hospital mortality. Each score was entered into a separate binary logistic regression model; discrimination was assessed with receiver operating characteristic curves and calibration with the Hosmer–Lemeshow test.

Results. Each score was significantly associated with mortality (p < 0.001). ISS had the highest area under the curve (AUC 0.88, 95% CI 0.81–0.95; odds ratio [OR] 1.15, 95% CI 1.09–1.21), followed by RTS (AUC 0.83, 95% CI 0.75–0.91; OR 0.45, 95% CI 0.32–0.63) and SI (AUC 0.76, 95% CI 0.67–0.85; OR 4.12, 95% CI 2.15–7.89). ISS differed significantly from SI (DeLong p = 0.014) but not from RTS (p = 0.238). Optimal cut-offs were ISS ≥ 29, RTS ≤ 6.95, and SI ≥ 1.05. Hosmer–Lemeshow tests were not significant (p > 0.05).

Conclusion. ISS had the highest AUC, while RTS and SI allow rapid bedside assessment. A staged approach combining immediate physiological scores with later anatomical scoring merits prospective testing in unselected trauma patients.