The Revised Trauma Score (RTS) condenses three vital signs — level of consciousness, blood pressure, and breathing rate — into a single physiologic severity score for trauma patients. Because it produces two related but distinct numbers, the triage variant and the weighted variant, it is easy to use one where the other belongs. This article explains how each is derived, what each is actually used for, and where the score's limits lie.

How the Revised Trauma Score Was Developed

Champion, Sacco, Copes, Gann, Gennarelli, and Flanagan published the Revised Trauma Score in the Journal of Trauma in 1989 as a refinement of the original 1981 Trauma Score. The revision adjusted the respiratory rate and systolic blood pressure breakpoints, which analysis of outcome data showed discriminated survival better than the original ranges, and dropped the original score's respiratory-effort component in favor of a cleaner three-variable design.

Each of the three physiologic measures — Glasgow Coma Scale total, systolic blood pressure, and respiratory rate — is translated into a coded value from 0 to 4 using published range tables, rather than used in its raw units. Coding puts three very differently scaled measurements (a 3-15 point neurologic scale, a blood pressure in mmHg, and a breathing rate in breaths per minute) onto a common footing so they can be combined into one score.

Triage RTS vs. Weighted RTS

The two RTS variants share the same three coded inputs but serve different purposes. Triage RTS is the unweighted sum of the three codes (range 0-12) — simple enough to calculate in the field without a calculator, which is exactly the point. It gives EMS providers and trauma teams a fast, reproducible physiologic severity marker to factor into transport and triage decisions alongside anatomic injury and mechanism-of-injury criteria.

Weighted RTS applies fixed coefficients (0.9368 for GCS, 0.7326 for SBP, 0.2908 for RR) derived through logistic regression against outcome data, producing a score from 0 to 7.8408. The unequal coefficients reflect that GCS carried the strongest independent association with survival in the derivation data, followed by SBP and then RR. Weighted RTS is not meant for bedside triage — it exists specifically as one of the inputs to statistical survival-prediction models, most notably TRISS.

How Weighted RTS Feeds Into TRISS and Survival Prediction

TRISS (Trauma and Injury Severity Score) is a logistic regression model that combines weighted RTS with the Injury Severity Score (an anatomic injury severity measure), patient age, and injury mechanism (blunt vs. penetrating) to estimate a probability of survival. Because TRISS requires all four inputs together, weighted RTS by itself does not translate into a specific survival percentage — this calculator computes the weighted RTS value but stops short of a TRISS calculation, since the additional inputs are outside its scope.

In practice, weighted RTS is used far more often in trauma registries, quality-improvement audits, and research than at the bedside, where the simpler Triage RTS (or newer tools) tends to guide real-time decisions.

Limits of the Revised Trauma Score

RTS is a physiologic score — it captures how deranged the patient's vital signs are at the moment of assessment, not what anatomic injuries caused that derangement. A patient can have a normal or near-normal RTS while harboring a serious internal injury that has not yet produced hemodynamic or neurologic compromise, which is why field triage protocols layer RTS alongside anatomic injury criteria (e.g. penetrating trauma to the torso, two or more long-bone fractures) and mechanism criteria (e.g. fall height, vehicle intrusion) rather than relying on RTS alone.

The score is also confounded by factors outside acute trauma: a patient with baseline dementia or intoxication may have a reduced GCS unrelated to head injury, and a patient on beta-blockers may not mount the expected tachycardic-then-hypotensive response reflected in SBP coding. Clinical judgment and serial reassessment remain necessary alongside any single RTS calculation, and no universal Triage RTS cutoff for trauma center transport is asserted here — follow the field triage protocol used by your EMS system or institution.