Authors' objectives: There is currently wide variation in prehospital major trauma triage across the National Health Service, with regional ambulance services using different triage tools, varying in format, structure and variables. To develop a national triage tool that is acceptable, usable, accurate, and optimises under- and over-triage. Major trauma is an important public health issue for the NHS. There are 20,000 cases annually in England, accounting for 5400 deaths, 8000 disabilities, £400M of healthcare costs and a £3.5B loss in economic output. Treatment in a major trauma centre (MTC) and the introduction of regional trauma systems have been associated with improved outcomes. Major trauma triage tools are used within English trauma networks to indicate which patients injured closest to a non-specialised hospital should be bypassed to a MTC, and to inform MTC emergency department (ED) pre-alert calls, facilitating patient reception into critical care areas for expedited assessment and resuscitation. Only a small fraction of the 1.25 million patients attended by ambulance services following injury represent major trauma, and identification may not always be obvious at the scene of incident. Bypassing and pre-alerting patients to MTCs without the potential to benefit (‘over-triage’) will waste resources and inconvenience patients. Conversely, failing to recognise appropriate patients with serious injury (‘under-triage’) could result in transport to non-specialist hospitals, resulting in less effective treatment and worse outcomes. Triage tools must therefore optimise the balance between under- and over-triage. There is currently wide variation in major trauma triage across the English NHS, with each regional ambulance service using a triage tool differing in format, structure, variables and cut points. This variability may contribute to inefficient care, unequal access to MTC treatment and suboptimal outcomes. Furthermore, as ambulance service and regional trauma network districts do not fully overlap, the use of multiple triage tools within a trauma network could present operational challenges. Consequently, the National Institute for Health and Care Excellence (NICE) recommended research to develop a national major trauma triage tool to improve patient outcomes and reduce costs. The Major Trauma Triage Tool Study (MATTS) project aimed to develop an accurate, acceptable and usable pre-hospital triage tool to identify patients with major trauma who could benefit from expedited MTC care in English trauma networks, optimising the trade-off between under- and over-triage. Specific objectives were to: Identify current major trauma triage tools and characterise their content. Review the evidence on performance of existing triage tools. Investigate user perspectives on major trauma triage tools and processes. Determine the optimal trade-offs between triage tool performance, costs and clinical outcomes. Define which patients benefit from expedited MTC care. Develop a new triage tool through expert consensus. Validate the diagnostic accuracy of expert derived and existing major trauma triage tools. Identify a candidate triage tool with optimal performance. Evaluate system-level performance of the implemented optimal triage tool, including identification of major trauma cases and compliance. Determine the usability and acceptability of the implemented triage tool. Evaluate the cost-effectiveness of triage using alternative triage tools.

Authors' results and conclusions: In Phase 1, document analysis identified 19 United Kingdom triage tools and 34 published international tools. The systematic review demonstrated limited diagnostic accuracy of triage tools in the elderly, with divergent real-life triage decisions. The reference standard included the need for critical trauma-related interventions, significant individual anatomical injuries, burden of multiple minor injuries and specific patient attributes. Decision-analytic modelling indicated that high-specificity triage tools were favoured. Triage tool simplicity and the option for clinical judgement were valued by stakeholders, but real-world triage was a multifaceted, nonlinear, dynamic and multiagency process. Following review of Phase 1 evidence, a three-step Major Trauma Triage Study candidate triage tool targeting relatively higher specificity was developed through expert consensus. The Phase 2 case–cohort sample included 2757 patients, with a weighted prevalence of major trauma of 3.1% (95% confidence interval 2.3% to 4.0%). The Major Trauma Triage Study tool performed optimally compared to under- and over-triage targets (sensitivity 37.3%, specificity 95.1%). In Phase 3, the newly implemented Major Trauma Triage Study triage tool was received favourably by stakeholders. Prehospital triage decisions using the new tool demonstrated a sensitivity of 55.3% (95% confidence interval 51.8% to 58.7%) and specificity of 94.3% (95% confidence interval 94.1% to 94.6%, n = 38,010, 2.2% prevalence of major trauma). Minimal differences were apparent between the costs (£149) and benefits (0.006 quality-adjusted life-years) of triage decisions, regardless of the triage tool used, reflecting similar real-life triage accuracy. However, the new Major Trauma Triage Study tool appeared cost-effective when theoretical triage tool performance was examined, demonstrating an incremental cost effectiveness ratio of £21,163. The Major Trauma Triage Study triage tool performed optimally, targeted an appropriate under-/over-triage trade-off, and was perceived to perform well by stakeholders. National implementation could ensure evidence-based, standardised and cost-effective triage. In Phase 1, the document analysis identified 53 major trauma tools using 173 distinct triage variables. Wide variation was apparent in format, number of triage variables, thresholds, scope for clinical judgement and relative diagnostic accuracy (high sensitivity vs. high specificity). Fifteen studies were included in the systematic review of triage tools in older people. Estimates for sensitivity and specificity were highly variable, with sensitivity estimates ranging from 19.8% to 95.5% for theoretical accuracy, and 57.7% to 83.3%, for real-life triage performance. Specificity results were similarly diverse ranging from 17.0% to 93.1%, and 46.3% to 78.9%, respectively. Most studies had unclear or high risk of bias, and applicability concerns. Overall, sensitivity and specificity appeared to be lower than that reported in systematic reviews examining younger adults. Decision-analytic modelling indicated that high-specificity triage tools were favoured. At a willingness-to-pay (WTP) threshold of £20,000 per quality-adjusted life-year (QALY) gained, the most cost-effective triage tool would have low sensitivity (28.0%), but high specificity (89.0%). However, results were sensitive to assumptions regarding MTC effectiveness and costs. A total of 81 questionnaires, and 6 focus groups including 62 participants, were completed. Current major trauma triage was perceived as performing well overall, with simple, ‘stepped’ structure of triage tools and the option for clinical judgement valued, leaving limited areas for further optimisation. Real-world triage was more complex than application of a triage tool checklist, with a variable, multifaceted, non-linear, dynamic and multiagency process evident. A reference standard for patients who would benefit from expedited MTC care was defined through expert consensus, comprising domains of need for critical interventions; presence of significant individual anatomical injuries; burden of multiple minor injuries; and important patient attributes. A three-step candidate MATTS triage tool was developed through expert consensus comprising physiology, anatomical injury and clinical judgement domains, with triage variables assessed in parallel. The triage tool targeted relatively higher specificity, defined inclusion criteria and variable definitions, and incorporated remote decision support. In Phase 2, the case–cohort sample consisted of 2757 patients, including 928 primary reference standard positive patients {major trauma prevalence 3.1% [95% confidence interval (CI) 2.3% to 4.0%]}. The MATTS triage tool (sensitivity 37.3%, specificity 95.1%) performed optimally, with accuracy closest to previously established under- and over-triage targets. The Phase 3 cohort study included 38,010 injured patients with a 2.2% prevalence of major trauma. Prehospital triage decisions using the new MATTS triage tool demonstrated a sensitivity of 55.3% (95% CI 51.8% to 58.7%) and specificity of 94.3% (95% CI 91.4 to 94.6%). There was evidence of triage tool use in a minority of patients (6.3%), with senior clinical advice sought in 9.3% of patients. Triage decisions were broadly unchanged before and after implementation of the MATTS tool (WMAS: Phase 2 sensitivity 48.3%/specificity 97.7% vs. Phase 3 : 59.0%/96.0%, p 

Authors' methods: A three-phase research programme, comprising Phase 1: development of a new triage tool by expert consensus informed by existing evidence, a systematic review of elderly triage, document analysis of current tools, decision-analytic modelling, expert consensus definition of a major trauma reference standard, and a qualitative examination of current triage; Phase 2: case–cohort study validating triage tools identified and developed in Phase 1, with identification of an optimally performing candidate triage tool; Phase 3: evaluation of the candidate triage tool following implementation, including cohort study investigating accuracy of triage decisions, cost-effectiveness analysis, and examination of user experiences. English regional trauma networks served by the South-Western, West Midlands, Yorkshire and London Ambulance Services. Phase 2 case–cohort study and Phase 3 cohort studies performed between 1 November 2019 and 28 February 2020, and 1 November 2021 and 15 May 2022, respectively. Injured patients presenting to ambulance services in participating regional trauma networks. Significant variation in National Health Service ambulance service and trauma network configurations could limit the generalisability of results. The MATTS project was conducted in three phases. In Phase 1, preparatory background research was conducted to inform the development of a new major trauma triage tool, comprising: a document analysis of existing tools to highlight possible designs and potential triage variables; a systematic review of triage tools in older people to supplement recently published reviews focusing on adults and children; decision-analytic modelling evaluating the cost-effectiveness of different triage tools and identifying the optimal target trade-off between under- and over-triage; a survey and focus groups to explore patient and clinician perspectives of current major trauma triage; and an expert consensus process to develop a relevant reference standard, defining the population of major trauma cases requiring expedited MTC care. Phase 1 culminated in the development of a candidate national triage tool through expert consensus (the ‘MATTS tool’). In Phase 2, the theoretical diagnostic accuracy of existing triage tools identified in Phase 1 and the MATTS triage tool developed through expert consensus were examined. A diagnostic case–cohort study was performed between November 2019 and February 2020 in four English regional trauma networks. Consecutive injured patients presenting to participating ambulance services were included and matched to data from the Trauma Audit and Research Network (TARN) trauma registry. The theoretical accuracy of 22 adult major trauma triage tools, including the newly developed MATTS tool, was evaluated, against the MATTS reference standard for major trauma. Index tests were assessed according to objective ambulance service data, regardless of the final triage decision or hospital destination. In Phase 3, the MATTS triage tool was implemented into practice by Yorkshire Ambulance Service NHS Trust (YAS) and West Midlands Ambulance Service University NHS Foundation Trust (WMAS) who collectively serve six English regional trauma networks. Consecutive injured patients between 1 November 2021 and 15 May 2022 were included in a multicentre, prospective cohort study, with nested case–cohort substudy. Electronic data from ambulance service patient report forms were linked to data from the TARN registry. The accuracy of prehospital triage decisions, in terms of conveyance to a MTC with an ED pre-alert, was calculated against the MATTS reference. Theoretical triage tool accuracy and triage tool use were also examined. Additional Phase 3 studies included an uncontrolled before-and-after study comparing triage accuracy pre and post implementation, a survey and focus groups to explore user experiences, and an economic evaluation investigating the cost-effectiveness, of the new triage tool.

Project Status: Completed

URL for project: https://www.journalslibrary.nihr.ac.uk/programmes/hta/17/16/04

Year Published: 2026

URL for published report: https://www.journalslibrary.nihr.ac.uk/hta/ALPE8857

URL for additional information: English

English language abstract: An English language summary is available

Publication Type: Full HTA

Country: England, United Kingdom

DOI: 10.3310/ALPE8857

Organisation Name: NIHR Health Technology Assessment programme

Contact Address: NIHR Journals Library, National Institute for Health and Care Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton Science Park, Southampton SO16 7NS, UK

Contact Name: journals.library@nihr.ac.uk

Contact Email: journals.library@nihr.ac.uk