Background The third international consensus definition for sepsis recommended use of a new prognostic tool, the quick Sequential Organ Failure Assessment (qSOFA), based on its ability to predict inhospital mortality and prolonged intensive care unit (ICU) stay in patients with suspected infection. While several studies have compared the prognostic accuracy of qSOFA to the Systemic Inflammatory Response Syndrome (SIRS) criteria in suspected sepsis, few have compared qSOFA and SIRS to the widely used National Early Warning Score (NEWS).

Methods This was a retrospective cohort study carried out in a UK tertiary centre. The study population comprised emergency admissions in whom sepsis was suspected and treated. The accuracy for predicting inhospital mortality and ICU admission was calculated and compared for qSOFA, SIRS and NEWS.

Results Among 1818 patients, 53 were admitted to ICU (3%) and 265 died in hospital (15%). For predicting inhospital mortality, the area under the receiver operating characteristics curve for NEWS (0.65, 95% CI 0.61 to 0.68) was similar to qSOFA (0.62, 95% CI 0.59 to 0.66) (test for difference, P=0.18) and superior to SIRS (P<0.001), which was not predictive. The sensitivity of NEWS≥5 (74%, 95% CI 68% to 79%) was similar to SIRS≥2 (80%, 95% CI 74% to 84%) and higher than qSOFA≥2 (37%, 95% CI 31% to 43%). The specificity of NEWS≥5 (43%, 95% CI 41% to 46%) was higher than SIRS≥2 (21%, 95% CI 19% to 23%) and lower than qSOFA≥2 (79%, 95% CI 77% to 81%). The negative predictive value was 88% (86%–90%) for qSOFA, 86% (82%–89%) for SIRS and 91% (88%–93%) for NEWS. Results were similar for the secondary outcome of ICU admission.

Conclusion NEWS has equivalent or superior value for most test characteristics relative to SIRS and qSOFA, calling into question the rationale of adopting qSOFA in institutions where NEWS is already in use.