qSOFA Score Calculator

Calculate the quick SOFA (qSOFA) score for bedside infection-risk assessment. Uses 3 simple criteria to flag patients with suspected infection who may need broader reassessment.

About the qSOFA Score Calculator

The quick SOFA (qSOFA) score is a bedside clinical tool introduced as part of the Sepsis-3 consensus definitions (2016) to flag patients with suspected infection who are at increased risk for poor outcomes. Using only three criteria — systolic blood pressure ≤100 mmHg, respiratory rate ≥22, and Glasgow Coma Scale <15 — it requires no laboratory testing and can be assessed in seconds.

qSOFA ≥2 is associated with a higher risk of in-hospital mortality compared with qSOFA <2. The score is best used as a prompt for fuller reassessment, including whether organ dysfunction may be present and whether local escalation pathways should be reviewed. Importantly, qSOFA is a screening tool, not a diagnostic criterion for sepsis — the Sepsis-3 definition still requires documented organ dysfunction (SOFA increase ≥2) in the setting of infection.

The simplicity of qSOFA makes it useful for initial triage in emergency departments, hospital floors, and resource-limited settings where laboratory results may not be immediately available.

Why Use This qSOFA Score Calculator?

The prior SIRS criteria (temperature, heart rate, respiratory rate, white blood cell count) were highly sensitive but often nonspecific. qSOFA is narrower and is mainly used to highlight a higher-risk bedside picture rather than to diagnose sepsis on its own.

As a no-lab bedside tool, qSOFA can help structure early reassessment before additional results return, especially when the clinical question is whether the patient may need closer observation or broader sepsis workup.

How to Use This Calculator

  1. Measure systolic blood pressure and evaluate whether it is ≤100 mmHg.
  2. Count respiratory rate and evaluate whether it is ≥22 breaths/minute.
  3. Assess Glasgow Coma Scale — is GCS less than 15?
  4. Sum the points: each criterion present = 1 point (range 0-3).
  5. Score ≥2: treat this as a higher-risk bedside signal and review fuller organ-dysfunction assessment in context.
  6. Score <2 does NOT exclude sepsis — continue monitoring if infection is still suspected.

Formula

qSOFA Score = Sum of: SBP ≤100 mmHg: 1 point RR ≥22/min: 1 point GCS <15: 1 point Range: 0-3 0: Lower bedside risk signal (<3% mortality) 1: Intermediate bedside risk signal (~10% mortality) ≥2: Higher bedside risk signal (24%+ mortality) — review for possible organ dysfunction

Example Calculation

Result: qSOFA 3/3 — High Risk

All three criteria are present: SBP 90 (≤100), RR 24 (≥22), and GCS 14 (<15). That places the patient in the highest qSOFA band and should prompt broader review for organ dysfunction and escalation using the local sepsis pathway.

Tips & Best Practices

Sepsis-3 Definition Framework

Sepsis-3 (2016) redefined sepsis as "life-threatening organ dysfunction caused by a dysregulated host response to infection." This replaced the prior SIRS-based definition. Key elements remain: sepsis = infection + SOFA ≥2. Septic shock = sepsis + vasopressor requirement for MAP ≥65 + lactate >2 despite adequate resuscitation. qSOFA is best viewed as a quick bedside flag that can prompt fuller SOFA-based reassessment.

Why qSOFA Is Still Useful

qSOFA can be calculated immediately, before laboratory data return, and helps structure early bedside concern when infection is on the differential. It is not a treatment algorithm, but it can help frame which patients may need closer observation, broader workup, or escalation discussions.

Controversies

qSOFA has been criticized for: (1) lower sensitivity than SIRS for identifying sepsis, (2) not incorporating temperature or white count, and (3) variable performance across validation cohorts. Some guidelines still prefer broader early-warning systems such as NEWS for frontline screening. The 2021 Surviving Sepsis Campaign treats qSOFA as one tool among many, not as a standalone gatekeeper.

Sources & Methodology

Last updated:

Methodology

This calculator assigns one point each for systolic blood pressure of 100 mm Hg or less, respiratory rate of 22 per minute or greater, and altered mentation, then sums the total into the standard 0-3 qSOFA score. The result is presented as a bedside prompt for further sepsis evaluation, especially the need to assess organ dysfunction with the full SOFA framework and to escalate infection management when clinically indicated.

The page does not treat qSOFA as a diagnosis of sepsis. A score below 2 does not exclude sepsis, and a score of 2 or more is meant to highlight increased risk of poor outcome in patients with suspected infection rather than to replace broader clinical assessment or hospital protocols.

Sources

Frequently Asked Questions

Does qSOFA replace SIRS for diagnosing sepsis?

qSOFA replaces SIRS as a bedside SCREENING tool, but neither qSOFA nor SIRS are diagnostic. The Sepsis-3 definition of sepsis requires: (1) suspected or confirmed infection PLUS (2) acute organ dysfunction as measured by SOFA increase ≥2. qSOFA identifies patients who should be evaluated for this organ dysfunction.

Can qSOFA miss sepsis?

Yes. qSOFA has moderate sensitivity (~60-70%) but high specificity for predicting poor outcomes. A qSOFA <2 does NOT rule out sepsis — patients with suspected infection and qSOFA <2 may still have sepsis and should continue to be monitored. qSOFA is better at predicting mortality than at diagnosing sepsis.

What is the hour-1 sepsis bundle?

The 2018 Surviving Sepsis Campaign hour-1 bundle groups common early sepsis-management steps such as lactate measurement, blood cultures before antibiotics, early antimicrobials, and fluid resuscitation for shock states. This calculator mentions the bundle only as background context; bedside management still depends on the full clinical picture and local protocols.

How does qSOFA differ from NEWS/MEWS?

qSOFA uses 3 criteria without labs and was designed specifically for infection. NEWS (National Early Warning Score) and MEWS use 6-7 vital sign parameters and are designed for general clinical deterioration, not specifically sepsis. Some studies suggest NEWS may outperform qSOFA for sepsis screening on general wards because it uses more parameters.

Should qSOFA be used in the ICU?

qSOFA was validated primarily for patients outside the ICU (ED, floor, outpatient). In the ICU, the full SOFA score should be used because ICU patients often meet qSOFA criteria from baseline critical illness. The Sepsis-3 guidelines specifically recommend qSOFA for non-ICU settings.

What about lactate as a screening tool?

Serum lactate ≥2 mmol/L is an important marker of tissue hypoperfusion in sepsis. However, lactate requires a blood draw and processing time. qSOFA is complementary — it provides immediate bedside assessment while lactate results are pending. Elevated lactate with qSOFA ≥2 identifies the highest-risk patients.

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