Team
health

Revised Trauma Score Calculator

The Revised Trauma Score (RTS) is a physiological severity index used in emergency departments and trauma centres to rapidly stratify patient risk. It combines three vital measurements—Glasgow Coma Scale, systolic blood pressure, and respiratory rate—into a single prognostic value. Emergency physicians and trauma surgeons rely on RTS to guide triage decisions, resource allocation, and family counselling. A single calculation takes seconds and correlates directly with mortality outcomes.

Last updated:

Creators Łucja Zaborowska, MD, PhD
2,898 people find this calculator helpful

How Trauma Disrupts Physiology

Severe injury triggers a cascade of physiological derangement. Tissue damage causes cellular ischaemia, inflammatory mediators flood the bloodstream, and perfusion to vital organs deteriorates. The body compensates by increasing heart rate and cardiac output, but as shock deepens, consciousness deteriorates, blood pressure falls, and breathing becomes shallow or irregular.

The magnitude of these changes reflects injury severity. A patient with a Glasgow Coma Scale of 15 and normal vitals has sustained minimal physiological insult. One with a GCS of 5, hypotensive at 70 mmHg, and gasping at 35 breaths per minute faces profound derangement and significantly reduced survival odds.

This is why a single number matters: it quantifies the body's physiological response in a way that bypasses diagnostic uncertainty and focuses on what emergency clinicians can measure immediately.

The Revised Trauma Score Equation

RTS combines three coded clinical variables, each weighted by a coefficient derived from logistic regression analysis of large trauma databases. The weighting reflects how strongly each variable predicts mortality.

RTS = (0.9368 × GCS code) + (0.7326 × SBP code) + (0.2908 × RR code)

GCS coding: 13–15 = 4; 9–12 = 3; 6–8 = 2; 4–5 = 1; 3 = 0

SBP coding: >89 = 4; 76–89 = 3; 50–75 = 2; 1–49 = 1; 0 = 0

RR coding: 10–29 = 4; >29 = 3; 6–9 = 2; 1–5 = 1; 0 = 0

  • GCS code — Glasgow Coma Scale score mapped to 0–4 based on severity bands
  • SBP code — Systolic blood pressure mapped to 0–4 according to shock severity
  • RR code — Respiratory rate mapped to 0–4 based on adequacy of ventilation

Understanding Your RTS Result

RTS ranges from 0 to 7.8408. The threshold of 4.0 is critical: patients scoring 4 or below meet criteria for transfer to a designated trauma centre, as mortality risk becomes substantial.

  • RTS 0–2: Severe derangement, mortality risk >80%
  • RTS 3–4: Moderate-to-severe injury, mortality 40–60%, centre-level care mandatory
  • RTS 5–6: Moderate injury, mortality 8–20%, close monitoring required
  • RTS 7+: Minor physiological derangement, mortality <5%, may be managed at any level

An unconscious patient (GCS 5) with blood pressure 80 mmHg and respiratory rate 30 per minute receives coded values of 1, 3, and 3 respectively, yielding an RTS of approximately 4.0—a 60% survival probability threshold where trauma centre admission is non-negotiable.

Common Pitfalls and Considerations

RTS is rapid and reproducible, but several clinical realities shape its interpretation:

  1. Coding errors skew results — RTS is only as accurate as the coded values entered. A Glasgow Coma Scale of 8 codes as 2, not 3. Misassignment changes the entire result. Always verify GCS, blood pressure, and respiratory rate before coding.
  2. Timing matters in resuscitation — RTS calculated at scene may differ from RTS in the ED after fluids and oxygen. Early hypotension and tachypnoea due to hypovolaemia often improve with resuscitation. Re-calculating RTS after stabilisation may yield a higher score and different management recommendations.
  3. RTS is not a standalone decision tool — RTS guides triage and prognosis but does not replace clinical judgment or detailed anatomical assessment. A patient with an RTS of 5 but severe head injury may still require neurosurgical evaluation at a trauma centre.
  4. Pre-hospital reporting accuracy varies — Paramedics at the roadside may estimate blood pressure or respiratory rate under stress or poor lighting. Hospital staff may record slightly different values. Small measurement errors can shift coded values and alter RTS by 0.5–1.0 points.

Historical Context and Clinical Use

The Revised Trauma Score evolved from the original Trauma Score developed by Champion and colleagues in the 1980s. It refined the earlier version by incorporating logistic regression coefficients that better predict mortality across diverse trauma populations.

Today, RTS remains embedded in many trauma activation protocols, pre-hospital triage algorithms, and research registries. It integrates easily into electronic health records and requires no laboratory tests—only bedside assessment. Many trauma centres use RTS alongside the Injury Severity Score (ISS) and mechanism of injury to form a complete triage picture.

RTS is particularly valuable in austere or under-resourced settings where advanced imaging is unavailable. A paramedic or junior clinician with a stopwatch, blood pressure cuff, and knowledge of the Glasgow Coma Scale can calculate prognosis in seconds.

Frequently Asked Questions

What is the difference between RTS and ISS?

RTS is a physiological score based on vital signs and consciousness at the moment of assessment; it predicts mortality and guides immediate triage. ISS is an anatomical score based on injury location and severity, calculated from imaging and clinical examination after full assessment. RTS is used for rapid triage in the field or ED; ISS is used for research, quality assurance, and longer-term outcome comparison. Most trauma centres use both together.

Can RTS be calculated before reaching hospital?

Yes. Paramedics and pre-hospital providers routinely calculate or estimate RTS at the scene using observed GCS, blood pressure, and respiratory rate. Pre-hospital RTS is used to activate trauma alerts and inform receiving hospitals of the patient's condition. However, pre-hospital values may be approximate; the ED team will re-assess and calculate a more precise score after baseline stabilisation.

What if a patient is on mechanical ventilation when RTS is calculated?

If the patient is intubated and sedated, the Glasgow Coma Scale cannot be accurately assessed—it will be reduced or unassessable. RTS is typically calculated pre-intubation or using the last known GCS before sedation. Once a patient is ventilated, RTS becomes less useful for ongoing clinical decisions; physicians rely instead on organ system assessment, imaging, and laboratory markers.

Does RTS apply to children?

RTS was developed and validated primarily in adult trauma populations. Children have age-adjusted vital signs, and their Glasgow Coma Scale interpretation differs slightly. Most paediatric trauma centres use modified scoring systems or age-specific thresholds. RTS should not be used in isolation for paediatric triage; age-appropriate trauma scales and clinical judgment are essential.

How reliable is the survival probability linked to RTS?

Survival probabilities associated with each RTS value come from large databases and are broadly applicable, but individual outcomes vary by patient age, comorbidities, injury pattern, and time to definitive care. A 65-year-old with an RTS of 5 has a lower overall survival probability than a 25-year-old with the same score. RTS provides a population-level estimate, not a guarantee for any individual patient.

Why does Glasgow Coma Scale carry the highest coefficient in the RTS formula?

The GCS coefficient (0.9368) is larger than blood pressure (0.7326) or respiratory rate (0.2908) because consciousness level is a potent predictor of mortality in trauma. Severe brain injury or shock-induced reduced consciousness carries high mortality independent of other factors. This weighting reflects decades of outcome data showing that neurological status is the strongest prognosticator among the three variables.

More health calculators (see all)

Smoking Recovery Calculator LDL Cholesterol Calculator Sleep Calculator Pregnancy Test Calculator APFT Calculator Absolute Reticulocyte Count Calculator EROA Calculator Age-Adjusted D-Dimer Calculator