Prehospital qSOFA Is Associated with 30-Day Mortality Within Emergency Department Triage Strata in Ambulance-Transported Adults with Suspected Infection: An Exploratory Three-Year Retrospective Cohort Study

Background/Objectives: Prehospital quick Sequential Organ Failure Assessment (qSOFA) screens poorly for sepsis, but an already-recorded field score may still inform the receiving physician. We asked whether it is associated with 30-day mortality within each emergency department (ED) triage classification, and what it adds to the arrival score. Methods: This study focused on a retrospective cohort of 1077 adults with suspected infection transported by ambulance to one Turkish university hospital ED, 2022 to 2024 (42.1% of 2558 eligible; most exclusions arose because the hospital episode record could not be retrieved). Patients were stratified by ED-arrival qSOFA classification (2 or more), then by prehospital classification. The primary outcome was 30-day mortality from hospital and national death records. The stratified analysis was post hoc. Results: Among 685 triage-negative patients, 30-day mortality was 13.9% when the field score had been below 2 and 26.0% when it had been 2 or more (adjusted odds ratio 2.06, 95% CI 1.28 to 3.25); among 392 triage-positive patients, 40.4% and 55.2% (1.84, 1.23 to 2.76), with no evidence of heterogeneity between strata (interaction odds ratio 0.85, 0.46 to 1.58). Adding the field value to the arrival value raised the area under the curve from 0.682 to 0.713. Added to a model of age, sex, comorbidity, lactate, oxygen saturation, heart rate, and temperature, it remained associated with death (1.71, 1.24 to 2.34) but changed the area under the curve by 0.007 (p = 0.23). In 27 selection scenarios returning the 1481 excluded patients, only a reversed association among them could nullify the triage-negative association, whereas the triage-positive association was nullified in 17 scenarios, 4 of them by a positive association. Conclusions: In this highly selected single-centre cohort, the prehospital qSOFA carried prognostic information not captured by the arrival score, with small incremental discrimination beyond routine ED data. The findings support preserving prehospital physiology at handover and justify prospective validation, not a change in disposition decisions.