What is a positive qSOFA score?

A qSOFA score of 2 or more out of 3 is considered positive and indicates high risk of sepsis-related poor outcomes outside the ICU. The three qSOFA criteria are: altered mentation (GCS <15), respiratory rate ≥22 breaths/min, and systolic blood pressure ≤100 mmHg. Each criterion scores 1 point. A score ≥2 should prompt investigation for organ dysfunction (full SOFA score) and consideration of the SSC Hour-1 Bundle.

What is qSOFA used for?

qSOFA (quick SOFA) is a bedside screening tool introduced in the Sepsis-3 consensus (2016) to identify patients outside the ICU — in the emergency department, general wards, or pre-hospital — who have suspected infection and are at high risk of poor outcomes including prolonged ICU stay and in-hospital death. It does not diagnose sepsis but identifies who needs urgent further evaluation with the full SOFA score.

qSOFA Score Calculator | Quick Sepsis Screening | Bedside Sepsis Tool

Q: What is qSOFA used for?

qSOFA (quick SOFA) is a bedside screening tool introduced in the Sepsis-3 consensus (2016) to identify patients outside the ICU — in the emergency department, general wards, or pre-hospital — who have suspected infection and are at high risk of poor outcomes including prolonged ICU stay and in-hospital death. It does not diagnose sepsis but identifies who needs urgent further evaluation with the full SOFA score.

qSOFA Score

Tap each criterion present. Score ≥2 = high-risk sepsis — initiate urgent workup.

🧠Altered Mentation

Glasgow Coma Scale <15 — any new confusion, drowsiness, agitation, or disorientation. Ask date, place, name. Check GCS formally if uncertain.

🫁Respiratory Rate ≥22 breaths/min

Count over 60 seconds. Normal adult RR is 12–20/min. RR ≥22 reflects respiratory compensation or direct lung involvement. Ventilated patients: consider PaO₂/FiO₂ ratio.

📉Systolic BP ≤100 mmHg

Measure in both arms if discrepancy suspected. In known hypertensives, even a SBP of 110–120 may represent significant hypotension from their baseline. Correlate with MAP.

qSOFA Score (max 3)

Score 0 — Low risk

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Sepsis Risk

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Sepsis-3

In-Hospital Mortality

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qSOFA — Complete Clinical Guide

The quick Sequential Organ Failure Assessment (qSOFA) score was introduced by the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3) in February 2016, published simultaneously in JAMA by Singer et al. It was designed as a simple bedside tool — requiring no laboratory investigations — to identify adult patients outside the intensive care unit who have suspected infection and are at high risk of prolonged ICU admission, in-hospital death, or other poor outcomes.

The development of qSOFA arose from a systematic review of over 1.3 million patient encounters in three large US health system databases. The three criteria — altered mentation, respiratory rate ≥22 breaths/min, and systolic blood pressure ≤100 mmHg — were selected from the full SOFA score as the variables with the strongest independent predictive value for in-hospital mortality in suspected infection outside the ICU. Each criterion scores 1 point, giving a maximum total of 3.

The Three qSOFA Criteria in Detail

Altered mentation (GCS <15): Any change from the patient's normal baseline mental state. This includes new confusion, disorientation, drowsiness, restlessness, or agitation. Ask: "What is today's date?", "Where are you?", "What is your name?" — failure on any suggests altered mentation. A GCS of 14 (even mild drowsiness) counts as positive. This criterion reflects early encephalopathy from poor cerebral perfusion or direct CNS effects of sepsis mediators
Respiratory rate ≥22 breaths/min: Must be counted over a full 60 seconds at rest. Tachypnoea in sepsis reflects metabolic acidosis (compensatory hyperventilation), hypoxaemia from early lung involvement, or pain. RR is the most under-reported vital sign in clinical practice — studies show nurses commonly fail to count RR, estimating instead. Always count for a full minute
Systolic BP ≤100 mmHg: Hypotension reflects cardiovascular compromise from vasodilation and myocardial depression in sepsis. Even a reading of 100 mmHg is below the threshold. In chronically hypertensive patients (baseline SBP 160–180 mmHg), a SBP of 110 may represent clinically significant relative hypotension even though it does not trigger qSOFA

qSOFA Performance and Evidence

The original Seymour et al. 2016 derivation study showed that qSOFA ≥2 had a similar predictive validity for in-hospital mortality as the full SOFA score in patients outside the ICU, with an AUROC of approximately 0.81 compared to 0.74 for SIRS criteria in the same population. A qSOFA ≥2 was associated with a 3- to 14-fold increase in in-hospital mortality compared to qSOFA <2. The score performs best as a prognostic tool, not a diagnostic tool — it does not confirm sepsis but identifies who needs urgent evaluation.

qSOFA vs SIRS vs SOFA — When to Use Each

✅ Use qSOFA when…

Bedside rapid screen needed
No labs immediately available
ED triage or ward assessment
Pre-hospital sepsis screening
Deciding who needs urgent bloods

✅ Use full SOFA when…

ICU admission or review
Confirming sepsis definition
Tracking organ dysfunction trend
Research/audit purposes
Labs available — more accurate

Limitations of qSOFA

A 2018 meta-analysis by Serafim et al. (Critical Care Medicine) found that qSOFA had lower sensitivity (60%) than SIRS criteria (88%) for identifying sepsis, meaning it misses up to 40% of patients who will deteriorate. A negative qSOFA does NOT exclude sepsis — clinical judgement must always prevail. In patients on beta-blockers, the HR component of SIRS and tachypnoea of qSOFA may be blunted. In the elderly, altered mentation may be chronic (dementia) or difficult to assess acutely. In chronic kidney disease or liver disease patients, baseline creatinine or bilirubin elevations may confound the full SOFA interpretation.

For these reasons, qSOFA is best used as a rapid initial screen that, when positive (≥2), triggers full SOFA assessment, blood cultures, lactate, and consideration of the SSC Hour-1 Bundle — not as the sole arbiter of sepsis diagnosis. Clinical gestalt and nursing concern should override a negative qSOFA when sepsis is suspected on other grounds.

Sepsis-3 Definitions — Quick Reference

Sepsis: Suspected or confirmed infection + acute increase in SOFA score ≥2 from baseline (representing organ dysfunction). In-hospital mortality ~10%
Septic shock: Sepsis + vasopressors required to maintain MAP ≥65 mmHg + serum lactate >2 mmol/L despite adequate fluid resuscitation. In-hospital mortality >40%
qSOFA ≥2 without SOFA: Should prompt urgent investigation — check lactate, blood cultures, FBC, RFT, LFT, coagulation, blood gas. Does not confirm sepsis without evidence of organ dysfunction

SSC Hour-1 Bundle — Key Actions

Measure lactate — if >2 mmol/L, repeat at 2 hours. If >4 mmol/L, aggressive resuscitation and ICU referral
Blood cultures ×2 sets before antibiotics (do not delay antibiotics if cultures cause delay)
Broad-spectrum antibiotics within 1 hour of sepsis recognition
IV crystalloid 30 mL/kg for MAP <65 mmHg or lactate ≥4 mmol/L
Vasopressors (noradrenaline) if MAP <65 mmHg persists after fluids

Frequently Asked Questions

Related Calculators

⚠ Medical Disclaimer: qSOFA is a screening tool with limited sensitivity. A negative qSOFA does not exclude sepsis. Clinical judgement must always override the score. Any patient with suspected sepsis should be assessed with blood cultures, lactate, and full SOFA evaluation regardless of qSOFA result. Follow your institution's sepsis protocol.

qSOFA ScoreCalculator