qSOFA Score Calculator

The quick SOFA score compresses organ dysfunction screening into three bedside observations, each worth one point: systolic blood pressure of 100 mmHg or less, respiratory rate of 22 breaths per minute or more, and any alteration in mentation, operationally a Glasgow Coma Scale below 15. The total runs 0 to 3 and a score of 2 or more is the positive threshold. The three variables were not chosen on physiological reasoning but selected statistically - they were the bedside items that best discriminated in-hospital mortality among patients with suspected infection outside the ICU, and the cut points of 100 mmHg and 22 breaths per minute came directly from that modelling rather than from conventional vital-sign norms. Notably 22 is a lower and more sensitive respiratory threshold than the SIRS value of 20. The operating characteristics define how it should be used. qSOFA has good specificity, roughly 80 percent or higher, but sensitivity for adverse outcome of only about 50 to 60 percent, so a score of 0 or 1 does not exclude sepsis and a patient can deteriorate having never scored 2. The 2021 Surviving Sepsis Campaign guidelines issued a strong recommendation against using qSOFA as a single screening tool in preference to SIRS, NEWS, or MEWS. It is best read as a prognostic flag: among patients with suspected infection, a qSOFA of 2 or more identifies a group with roughly three to fourteen times the mortality of qSOFA under 2, and should trigger lactate measurement, blood cultures, and escalation - not as a rule-out.

qSOFA emerged from the Third International Consensus Definitions for Sepsis and Septic Shock, published in JAMA in February 2016 by a task force convened by the Society of Critical Care Medicine and the European Society of Intensive Care Medicine and chaired by Mervyn Singer and Clifford Deutschman. That task force redefined sepsis as life-threatening organ dysfunction caused by a dysregulated host response to infection, retired the terms SIRS-based sepsis and severe sepsis, and anchored organ dysfunction to an acute rise of 2 or more points in the SOFA score. Because SOFA requires laboratory values and is impractical outside intensive care, the task force commissioned a companion bedside tool. Christopher Seymour, Vincent Liu, Theodore Iwashyna, and colleagues published the derivation in the same 2016 issue of JAMA, mining electronic health records from roughly 1.3 million encounters across UPMC hospitals and validating against four external datasets including Kaiser Permanente Northern California. Among out-of-ICU patients with suspected infection, the three-variable model performed comparably to the full SOFA score for predicting mortality, and the task force named it qSOFA. It was contentious almost immediately: emergency medicine and infectious disease bodies criticized its low sensitivity for early sepsis, several large validation studies found it inferior to NEWS for screening, and by the 2021 guideline revision its recommended role had narrowed from screening to risk stratification.