Emergency and Critical Care

qSOFA Score Calculator: Bedside Sepsis Risk Screening

Q: Does qSOFA replace SIRS?

Not entirely. Sepsis-3 formally dropped SIRS as a mandatory criterion for sepsis, but many protocols retain SIRS as a parallel screening tool, since it is more sensitive though less specific.

Q: What should be done when qSOFA = 1?

Intermediate risk. Do not ignore it: reassess in 1-2 hours, especially if infection is suspected. Consider laboratory markers such as lactate, CRP, and procalcitonin.

Q: Can qSOFA be used in the ICU?

In the ICU, organ dysfunction is assessed with the full SOFA score. qSOFA is intended for use outside the ICU, when a quick decision is needed on whether to escalate care.

Q: Is qSOFA appropriate for outpatient use?

Yes, particularly in elderly patients and those with chronic illness. Any patient with qSOFA ≥ 2 should be referred to the hospital immediately, bypassing routine scheduling.

Quick bedside sepsis risk screening tool

Primary source: Singer M et al. JAMA 2016; 315(8): 801-810 (Sepsis-3)

Aleksandr A. Aulov, MD, internal medicine Last clinical review: April 28, 2026

Online calculation

Respiratory rate ≥ 22/min

Altered mentation (GCS < 15)

SBP ≤ 100 mm Hg

About this score

qSOFA (quick Sepsis-related Organ Failure Assessment) is a three-parameter bedside tool proposed by the Sepsis-3 consensus (Singer M et al, JAMA, 2016). The key idea is to identify, at the bedside and without laboratory testing, patients with suspected infection who have a high likelihood of prolonged ICU stay or death.

qSOFA does not diagnose sepsis and does not replace the full SOFA score. It is a screening step meant to trigger a cascade of investigations: lactate, procalcitonin, blood cultures, and assessment of organ dysfunction with the full SOFA score. Per the consensus, a score of ≥ 2 in a patient with suspected infection should prompt immediate consideration of sepsis as a diagnosis.

Critics of the score point to its limited sensitivity in the emergency department: meta-analyses show a sensitivity of around 50% at a specificity of 80%. For this reason, many hospitals combine qSOFA with SIRS criteria or NEWS2 to avoid missing early sepsis in younger patients with preserved physiologic reserve.

When to use

Any patient with suspected infection outside the ICU: emergency department, general medical ward, or outpatient visit.
Reassessment when a patient already being treated for infection deteriorates.
Prehospital triage by EMS crews.
Documenting the clinical rationale for activating a hospital sepsis protocol.

Parameters in detail

Respiratory rate ≥ 22/min

Respiratory rate ≥ 22/min is the most sensitive of the three components. Count for a full minute visually or with pulse oximetry; do not round off to "tachypneic."

Altered mentation (GCS < 15)

Any acute change in mental status, including drowsiness, lethargy, or disorientation. Formalized as GCS < 15 or inability to correctly answer standard orientation questions (name, place, date).

SBP ≤ 100 mm Hg

SBP ≤ 100 mm Hg is a stricter threshold than in CURB-65 (< 90 there), reflecting early hemodynamic instability before overt shock develops.

Clinical example

Case

A 67-year-old woman presents with right upper quadrant pain and fever of 38.9°C for three days. History of gallstone disease. On exam: BP 95/60 mm Hg, respiratory rate 24/min, drowsy, GCS 14 (E4 V4 M6). Scleral icterus.

Calculation

Respiratory rate ≥ 22 (+1) + GCS < 15 (+1) + SBP ≤ 100 (+1) = 3 points.

Interpretation and management

High risk of sepsis. Immediate actions: blood cultures ×2 before antibiotics, lactate, complete blood count and metabolic panel, empiric antibiotics within one hour, 30 mL/kg crystalloid bolus if hypotensive, and urgent ultrasound/CT to localize the source. The full SOFA score is calculated in parallel to confirm organ dysfunction.

Limitations and cautions

Low sensitivity for early sepsis; a patient with compensated organ dysfunction may score 0.
Not validated in children; pediatric patients require adapted scores (pSOFA, PEWS).
In patients with chronic hypotension, baseline cognitive impairment, or COPD, interpretation requires knowledge of the patient's baseline status.
qSOFA = 0 does not exclude sepsis: a full workup should proceed regardless of the score if clinical suspicion is high.

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Frequently asked questions

Does qSOFA replace SIRS?

Not entirely. Sepsis-3 formally dropped SIRS as a mandatory criterion for sepsis, but many protocols retain SIRS as a parallel screening tool, since it is more sensitive though less specific.

What should be done when qSOFA = 1?

Intermediate risk. Do not ignore it: reassess in 1-2 hours, especially if infection is suspected. Consider laboratory markers such as lactate, CRP, and procalcitonin.

Can qSOFA be used in the ICU?

In the ICU, organ dysfunction is assessed with the full SOFA score. qSOFA is intended for use outside the ICU, when a quick decision is needed on whether to escalate care.

Is qSOFA appropriate for outpatient use?

Yes, particularly in elderly patients and those with chronic illness. Any patient with qSOFA ≥ 2 should be referred to the hospital immediately, bypassing routine scheduling.

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Aleksandr A. Aulov Physician, internal medicine, Sechenov School — independent medical education platform. Calculators are compiled from the original publications and current clinical guidelines. Interpretation thresholds follow the source study unless stated otherwise.

This calculator is intended for healthcare professionals. Do not use it for self-diagnosis or self-treatment. Management decisions are made by the treating clinician based on the full clinical picture of the individual patient.