qSOFA Score Calculator
qSOFA Score Calculator
Flag suspected infection at higher risk of death or prolonged critical care using three bedside observations and no laboratory tests.
qSOFA Score
3 items → 0–3Respiratory rate 22 or more (1), altered mentation (1), systolic BP 100 mmHg or less (1)
Scoring
- Respiratory rate
- 22 breaths per minute or more
- Mentation
- any acute alteration — GCS below 15
- Systolic BP
- 100 mmHg or less
- high risk
- 2 or more of the three items, in a patient with suspected infection
Worked example
Respiratory rate 22 or more (1), altered mentation (1), systolic BP 100 mmHg or less (1)
1 + 1 + 1 = 3 points
3 is 2 or more → high risk
qSOFA versus SIRS and NEWS2 for screening
| Tool | Inputs | Role recommended by SSC 2021 |
|---|---|---|
| qSOFA | 3 bedside items, no labs | Prognostic marker once infection is suspected — NOT a screening tool |
| SIRS | 4 items, includes white cell count | Acceptable screening tool |
| NEWS2 | 7 routine observations | Preferred screening tool |
A prognostic marker, not a screening test
qSOFA — quick SOFA — was introduced alongside the Sepsis-3 definitions to flag patients with suspected infection who are at higher risk of dying or spending a prolonged stay in critical care, using nothing but three bedside observations: respiratory rate, mental state and systolic blood pressure. No blood test is required, which was the point — it was built for use outside intensive care, on the general ward and in the emergency department, where laboratory turnaround can be slow.
Its evidence base needs reading carefully. qSOFA is reasonably specific — a positive score in a patient with suspected infection does identify a group with materially worse outcomes — but it is not sensitive. A substantial proportion of patients who go on to deteriorate, need vasopressors or die score 0 or 1 at initial assessment, particularly early in their illness. Relying on it alone to decide who needs escalation misses people who need it.
The Surviving Sepsis Campaign’s 2021 guidelines are explicit on this point: they recommend against using qSOFA as a single screening tool for sepsis, preferring NEWS2 or SIRS for that purpose and reserving qSOFA as a prognostic marker once infection is already suspected, rather than as the test that raises the suspicion in the first place. A negative qSOFA must never be used to rule out sepsis or to stand down concern in a patient who otherwise looks unwell — the clinical picture, and a more sensitive tool, should decide that.
Frequently asked questions
What qSOFA score is high risk?
2 or 3 points out of 3. In a patient with suspected infection this identifies a substantially higher risk of death or a prolonged stay in critical care.
Can a low qSOFA rule out sepsis?
No. qSOFA is specific but not sensitive — many patients who go on to deteriorate score 0 or 1 at initial assessment. A negative qSOFA must not be used to stand down clinical concern.
Should qSOFA be used to screen for sepsis?
The Surviving Sepsis Campaign 2021 guidelines recommend against it. NEWS2 or SIRS are preferred for screening; qSOFA is better used as a prognostic marker once infection is already suspected.
What does a high qSOFA mean I should do?
Escalate assessment promptly — consider a full SOFA score, source control, cultures before antibiotics where feasible, and early senior or critical care review.
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References
- Seymour CW et al. Assessment of clinical criteria for sepsis: for the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016;315(8):762–74.
- Evans L et al. Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock 2021. Crit Care Med. 2021;49(11):e1063–143.
Medical Disclaimer: The tools and content provided here are for educational and reference purposes only. They are not intended to substitute for professional medical advice, diagnosis, or treatment. Clinical decisions should always be based on the comprehensive assessment of a qualified healthcare professional.