Nurse-Led Triage Protocols in Emergency and Trauma Care: A PRISMA-Guided Systematic Review

Abstract

Triage nurses are the first clinical decision-makers for most patients entering an emergency department (ED) or trauma centre, yet evidence on nurse-led triage is scattered across three literatures that are rarely read together: the reliability and accuracy of acuity scales applied by nurses, the effects of nurse-initiated protocols at triage, and nurse-led triage of injured patients. This PRISMA 2020-guided systematic review synthesises primary quantitative studies published between 2000 and 2025 across these three streams. Because bibliographic databases could not be queried from the review environment, records were identified through 170 structured web-search queries, citation searching of 18 prior reviews and evidence documents, and direct look-ups of Crossref, OpenAlex and OpenAIRE records, a constraint reported as a limitation. Of 161 unique candidate records, 112 studies met the eligibility criteria: 58 evaluated nurse-applied acuity scales, 41 evaluated nurse-initiated or nurse-led protocols and 13 evaluated nurse-led trauma triage. Across 46 agreement estimates, five-level scales applied by nurses showed moderate-to-substantial reliability (weighted κ mostly 0.6–0.9), with lower agreement for memory-based triage and for components of the Ottawa rules (κ 0.3–0.5). Under-triage ranged from 3% to 20% and over-triage from 4% to 54% depending on the reference standard, and sensitivity for immediate life-saving interventions in older adults was low (42–46%). Nurse-initiated analgesia, radiography, laboratory, sepsis and asthma protocols shortened time to treatment in every study that reported it, including seven randomised trials, with no serious adverse events attributed to the protocols; effects on ED length of stay were smaller and inconsistent. In trauma care, nurse clearance of the cervical spine with the Canadian C-Spine Rule missed no injuries in two large programmes, and under-triage fell when activation criteria were followed by a designated nurse, although over-triage remained high. Certainty is judged moderate for the direction of reliability and timeliness effects and low for accuracy, patient outcomes and trauma triage. Nurse-led triage protocols are reliable, safe and time-saving when backed by validated instruments, explicit authority and audit.