qSOFA Score Calculator

qSOFA Score Calculator for Critical Care. The clinically meaningful threshold is 2 or more of the 3 points. A qSOFA of 0 to 1 is reassuring for short-term risk but does not exclude sepsis, since the score is deliberately insensitive. A qSOFA of 2 or 3 marks a patient with suspected infection who is substantially more likely to have poor outcomes and should prompt urgent evaluation for organ dysfunction, lactate and cultures, source control, and consideration of higher-acuity care. qSOFA quantifies risk of a bad trajectory; it is not itself a diagnosis of sepsis, which under Sepsis-3 requires an acute rise in the full SOFA score of 2 or more points (associated with in-hospital mortality above 10 percent).

How this calculator works

The quick Sequential Organ Failure Assessment (qSOFA) awards one point each for three bedside findings in a patient with suspected infection: systolic blood pressure of 100 mmHg or lower, respiratory rate of 22 breaths/min or greater, and any altered mental status (a Glasgow Coma Scale below 15). The three items sum to a score of 0 to 3, requiring no laboratory tests, blood gas, or imaging. It was derived by Seymour and colleagues via multivariable logistic regression on electronic health records as a stripped-down surrogate for the full SOFA score, intended to flag infected patients at higher risk of death or prolonged ICU stay.

When to use this calculator

qSOFA is best used as a rapid prompt in non-ICU settings, the emergency department, general wards, and prehospital or out-of-hospital care, to identify adults with suspected infection who may deteriorate. In the derivation cohort its discrimination outside the ICU (AUROC 0.81) exceeded that of SOFA and SIRS. It should NOT be used as a screening trigger inside the ICU, where SOFA outperformed it (qSOFA AUROC only 0.66), nor in children, pregnancy, or as a rule-out test given its low sensitivity. Surviving Sepsis Campaign 2021 recommends against qSOFA as a sole screening tool.

Inputs used

  • Mental status
  • Systolic blood pressure
  • Respiratory rate

Clinical interpretation

The clinically meaningful threshold is 2 or more of the 3 points. A qSOFA of 0 to 1 is reassuring for short-term risk but does not exclude sepsis, since the score is deliberately insensitive. A qSOFA of 2 or 3 marks a patient with suspected infection who is substantially more likely to have poor outcomes and should prompt urgent evaluation for organ dysfunction, lactate and cultures, source control, and consideration of higher-acuity care. qSOFA quantifies risk of a bad trajectory; it is not itself a diagnosis of sepsis, which under Sepsis-3 requires an acute rise in the full SOFA score of 2 or more points (associated with in-hospital mortality above 10 percent).

Worked example

A 71-year-old with suspected pneumonia has SBP 96 mmHg (1 point), respiratory rate 26/min (1 point), and is oriented with GCS 15 (0 points). The qSOFA is 2. A score of 2 or more places this patient in the higher-risk band: relative to a score below 2, encounters with qSOFA at or above 2 carried a 3- to 14-fold increase in in-hospital mortality across baseline risk deciles. This should trigger escalation, closer monitoring, lactate measurement, and formal assessment for organ dysfunction (full SOFA) rather than confirming sepsis on its own.

Limitations and safety notes

The dominant weakness is poor sensitivity: many septic and even critically ill patients present with qSOFA below 2, so a low score must never be used to withhold workup or treatment. Numerous prospective ED studies since 2016 found qSOFA less sensitive than SIRS or NEWS for detecting sepsis, trading sensitivity for specificity. Altered mentation is confounded by baseline dementia, intoxication, and sedation, and the score performs worst in ICU populations, where it should not be used. It also gives no guidance in pediatrics, pregnancy, or immunosuppressed hosts with blunted physiology.

Frequently asked questions

Is a qSOFA of 2 or more the same as a diagnosis of sepsis?

No. A qSOFA of 2 or 3 identifies an infected patient at elevated risk of deterioration and should prompt investigation, but sepsis under Sepsis-3 is defined as life-threatening organ dysfunction, operationalized as an acute increase in the full SOFA score of 2 or more points.

Can I use qSOFA to rule out sepsis if the score is 0 or 1?

No. qSOFA is intentionally insensitive and misses many septic patients. A low score does not exclude serious infection, and clinical suspicion, lactate, and further assessment should still drive management.

Should qSOFA be used in the ICU?

No. In the derivation study SOFA discriminated in-hospital mortality far better than qSOFA among ICU encounters (AUROC 0.74 vs 0.66). qSOFA was designed for non-ICU and prehospital settings.

Why did the Surviving Sepsis Campaign move away from qSOFA?

Because of its low sensitivity, the 2021 Surviving Sepsis Campaign guidelines recommend against using qSOFA as a single screening tool for sepsis, favoring more sensitive tools such as NEWS or SIRS-based screening combined with clinical judgment.

Does altered mental status require a formal GCS?

The item is met by any GCS below 15, so any new confusion, drowsiness, or agitation counts as a point, though baseline cognitive impairment and other causes of altered consciousness can confound this component.

References

  • Seymour CW, Liu VX, Iwashyna TJ, et al. Assessment of Clinical Criteria for Sepsis: For the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016. PMID: 26903335.
  • Singer M, Deutschman CS, Seymour CW, et al. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016. PMID: 26903338.
  • Shankar-Hari M, Phillips GS, Levy ML, et al. Developing a New Definition and Assessing New Clinical Criteria for Septic Shock: For the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016. PMID: 26903336.
  • Evans L, Rhodes A, Alhazzani W, et al. Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock 2021. Crit Care Med. 2021. PMID: 34605781.

Editorial review and citation methodology

Reviewed by the Quick Medical Calculator Editorial Team. Last reviewed: March 30, 2026. The review checks calculator inputs, intended population, interpretation, limitations, and source alignment.

  • Prefer original validation studies for scoring systems and prediction tools.
  • Use current specialty society guidance, transplant allocation policy, public health guidance, or regulator resources when they govern clinical use.
  • Include limitations and safety notes when a calculator is population-specific, context-dependent, or unsuitable as a standalone decision tool.

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