qSOFA (quick SOFA)

Methodology

qSOFA (Seymour 2016, Sepsis-3)

1 point each: RR ≥ 22, altered mentation, SBP ≤ 100

qSOFA identifies patients with suspected infection who are more likely to die or stay long in intensive care. It is not a diagnostic criterion for sepsis.

Who it is for

Adults with suspected infection outside the ICU.

Version

1.0.0

How this calculator works

Where the formula comes from

• qSOFA was derived by Seymour and colleagues (2016) for Sepsis-3 from 1.3 million electronic health record encounters at 12 Pennsylvania hospitals; 148,907 encounters with suspected infection were split into derivation and validation sets.^[1]
• It was confirmed in 4 external data sets of 706,399 encounters at 165 US and non-US hospitals.^[1]

The inputs

• One point each for respiratory rate 22/min or more, systolic blood pressure 100 mmHg or less and altered mentation (score 0–3).^[1]
• Sepsis-3 uses a qSOFA of 2 or more to identify patients with suspected infection who are more likely to have poor outcomes; it is a prompt to look for organ dysfunction, not a definition of sepsis.^[2]

Where accuracy falls (published evidence)

• In ICU patients with suspected infection, qSOFA (AUROC 0.66) predicted in-hospital death less well than SOFA.^[1]
• A systematic review of 410,000 patients found that qSOFA had poor sensitivity for short-term mortality.^[3]
• In infected patients outside the ICU, early warning scores such as NEWS and MEWS were more accurate than qSOFA for predicting death and ICU transfer.^[4]

What guidelines say

• The Surviving Sepsis Campaign 2021 recommends against using qSOFA, compared with SIRS, NEWS or MEWS, as a single screening tool for sepsis or septic shock.^[5]

Sources

1. 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;315(8):762–774. doi:10.1001/jama.2016.0288
2. Singer M, Deutschman CS, Seymour CW, et al. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016;315(8):801–810. doi:10.1001/jama.2016.0287
3. Lo RSL, Leung LY, Brabrand M, et al. qSOFA is a poor predictor of short-term mortality in all patients: a systematic review of 410,000 patients. J Clin Med. 2019;8(1):61. doi:10.3390/jcm8010061
4. Churpek MM, Snyder A, Han X, et al. Quick sepsis-related organ failure assessment, systemic inflammatory response syndrome, and early warning scores for detecting clinical deterioration in infected patients outside the intensive care unit. Am J Respir Crit Care Med. 2017;195(7):906–911. doi:10.1164/rccm.201604-0854OC
5. 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;49(11):e1063–e1143. doi:10.1097/CCM.0000000000005337

Compiled from the published sources above. Every statement was agreed independently by three AI research tools (Claude, ChatGPT, DeepSeek) and its source verified in PubMed or Crossref by the Hakeemly editorial team. Not reviewed by a doctor unless stated. Agreed on 2026-10-11

Worked example: how to calculate qSOFA

An illustration with sample values, worked out with the same method the tool above uses.

Limitations

• The Surviving Sepsis Campaign 2021 recommends against using qSOFA alone as a screening tool, compared with SIRS, NEWS or MEWS.

References

1. 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;315(8):762–774. doi:10.1001/jama.2016.0288
2. 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;49(11):e1063–e1143. doi:10.1097/CCM.0000000000005337