Triage of road injury casualties - the role of bystanders: a scoping review

Abstract

Background

Bystanders have the potential to be a critical component of the Road Injury Chain of Survival, particularly in the early phases of injury recognition, scene assessment, and emergency service activation. Their potential role in trauma triage remains underexplored. This scoping review aims to examine the existing evidence of the use of bystanders in triage—both laypersons and non-clinical professionals—during the prehospital phase of road injury and other trauma scenarios.

Methods

A systematic search was undertaken across MEDLINE, CINAHL, and the Psychology & Behavioural Sciences Collection using the EBSCO Host platform, with supplementary hand searches via Google Scholar and reference screening. Articles were included if they addressed triage by lay or professional bystanders (e.g. police, fire and rescue) in prehospital trauma settings. Data were extracted and synthesised using a descriptive analytical approach.

Results

Twenty-three studies were included. Bystanders demonstrated the ability to apply basic triage tools with moderate accuracy, although over-triage was common and under-triage rates often exceeded accepted thresholds. Several trauma training programmes in low-resource settings included triage components, leading to improvements in knowledge and confidence. Long-term retention and real-world clinical utility remain uncertain. Only one study directly evaluated bystander assessment of crash parameters; lay performance approached that of health professionals in some domains. Technological innovations such as video live-streaming from bystanders to emergency call handlers showed potential to enhance triage and situational awareness, though operational and ethical barriers remain.

Conclusions

Bystanders may have an expanded role in the triage and early assessment of trauma casualties, particularly in settings where formal EMS is limited or delayed. Within the Road Injury Chain of Survival, empowering bystanders through structured training and technology-enabled support could strengthen early links in the chain. Future research should focus on validating simplified triage approaches, evaluating training impact, and assessing outcomes related to both patient care and system efficiency.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13049-025-01455-7.

Background

Road injury remains the leading cause of death for those aged 5–29 years, and the most common cause of traumatic death across all age groups, accounting for around 1.2 million deaths per year [1]. Deaths occur disproportionately in Low-Middle Income Countries (LMICs) where prehospital care systems are not yet available or remain in their nascent stages [1, 2]. In these countries road injury casualties are often attended to and transported by lay-bystanders and non-clinical professionals (e.g. police officers) [3–5]. Prevalence of bystander assistance to trauma casualties is reported as high as 94% [6]. Development of prehospital medical services often starts with community based first-aid programs for lay persons [7].

In High Income Countries (HICs) with established pre-hospital care systems, bystanders are frequently present at the scene of traumatic injury and responsible for contacting emergency medical services (EMS). One UK study of pre-hospital trauma deaths showed bystanders were present prior to the arrival of an ambulance in 86% of cases in a rural setting and 96% of cases in an urban setting. In the vast majority of these cases bystanders were responsible for contacting EMS [8]. Other studies have recorded bystanders present in 58–97% of cases [9, 10].

Bystanders are an essential component of the first two links of the road injury chain of survival (Fig. 1), providing recognition of injury and activation of the EMS response, and may have a further role in the third link, providing immediate life saving treatment prior to EMS arrival [11]. The benefits of bystanders are already recognised for delivery of cardiopulmonary resuscitation (CPR), and more recently for delivery of immediate haemorrhage control in mass casualty incidents (MCI) [12].

Fig. 1.

Road injury chain of survival

Triage is the process by which patients are allocated resources and treatments according to the principle of ‘doing the most for the most’. In established prehospital care systems, the process of triage frequently begins with a bystander call to EMS. Key parameters are extracted through conversation and input by call-handlers into algorithmic decision trees [13]. Triage is necessary to ensure appropriate allocation of finite resources. Currently used systems such as advanced medical priority dispatch systems (AMPDS) tend towards being sensitive but not specific, thus increasing the risk of under- or over-triage; avoidance of which is essential for preventing avoidable morbidity and mortality while optimising resource allocation [14]. EMS triage is inherently reliant upon the information provided by callers which may be inaccurate, conflicting or duplicated [15].

For bystanders to be an effective part of the road injury chain of survival, we need to understand how to optimally utilise, empower and support them. In this scoping review we explore the role of bystanders in the triage of trauma casualties. Scoping review methodology was chosen due to the breadth and complexity of this particular topic. While our primary interest is road injury, due to the suspected paucity of specific evidence on this topic, we sought to gather evidence from across the spectrum of trauma care. We sought to evaluate:

1. The role bystanders play in the assessment & triage of trauma casualties.

2. The accuracy of bystander assessment and triage.

3. The usefulness of bystander assessment and triage for emergency medical services.

4. How to educate, empower, and utilise bystanders for triage of road injury casualties.

Synthesis of the existing evidence will provide valuable insights into the current landscape, identify areas of need, and inform future research.

Methods

This review was conducted in line with established scoping review methodology [16] and reported in accordance with PRISMA scoping review extension guidance (supplementary information). This study has been registered with Research Registry: UIN reviewregistry2031.

Definitions

In the absence of widely accepted nomenclature we use the following definitions:

Lay-person or lay-bystander

Individuals who may render assistance to trauma casualties but who do not belong to one of the professional classes which may be involved in the formal response to traumatic injury (i.e. police, fire & rescue, or EMS).

Professional-bystanders

Professionals who may render assistance to trauma casualties as part of a formal response to traumatic injury (i.e. police, fire & rescue) but are not classed as healthcare professionals.

Data sources

A systematic search of MEDLINE, CINAHL and Psychology & Behavioural Sciences Collection was undertaken using the EBSCO Host platform, with assistance from the South Tyneside & Sunderland NHS Foundation Trust Library Services. Additional hand searches of Google Scholar were conducted using keywords. Reference lists of studies selected for full text review were screened for additional relevant articles. Full search terms and keywords can be found in Supplementary Information.

Search strategy

The search strategy was refined through iterative cycles exploring different search terms in order to maximise information capture from the evidence base. Searches were conducted on 13/10/2024 without limits or restriction. Articles were retrieved and exported to Rayyan for removal of duplicates and screening [17]. Titles and Abstracts were screened collaboratively for eligibility by a team of three reviewers. Disagreements were resolved through collaborative discussion. Full text review, and subsequent reference list searches were conducted by the first author.

Data extraction & synthesis

Study characteristics and summary of results were extracted and collated using a Microsoft Excel (Microsoft Corporation, Redmond, USA) template. Categories of findings were identified inductively through an iterative process of data organisation rather than through formal thematic analysis, grouping similar study designs and findings to provide a structured overview of the literature. This process allowed for the identification of recurring patterns and commonalities without imposing a predefined coding framework, ensuring this synthesis remained broad and reflective of the available evidence.

Inclusion/exclusion criteria

Inclusion criteria included any original research, clinical trial, meta-analysis, guideline, consensus statement, or grey literature relating to the triage of trauma casualties in the prehospital environment by lay-persons and professional (non-clinical) responders such as Police, Fire & Rescue.

Articles exploring formal triage by emergency medical services or in-hospital triage; reviews, and non-English language articles were excluded.

Results

A total of 2110 unique articles were identified through database searches with a further 3 articles from hand searches, and 41 articles from reference list searches. After abstract screening, a total of 81 articles were retrieved for full text review. After application of inclusion and exclusion criteria, a total of 23 articles were included for review and evidence synthesis (Fig. 2). The geographic spread of evidence sources can be seen in Fig. 3.

Fig. 2.

Flow diagram demonstrating evidence sources and screening process

Fig. 3.

Global heatmap demonstrating geographic spread of included studies

To aid interpretation of these findings, results are presented across three key domains, aligned with our stated research aims. These domains are reflective of the predominant themes within the literature, and explore: the role of bystanders in triage; the accuracy of bystander triage; and the impact of training interventions on bystander triage capability.

Triage and the role of bystanders

Bystanders already have an established role within the road injury chain of survival, providing first contact with emergency care services thereby activating the emergency response. Here we explore ways to enhance this existing paradigm.

Identification of crash parameters

Crash parameters such as seatbelt use, intrusion and deformity of passenger compartments are associated with injury severity and may form part of triage and resource allocation protocols [18, 19]. Despite the potential value of bystander-reported crash parameters, only one study was identified that specifically assessed this capability (Table 1).

Table 1.

Triage & the role of bystanders - a summary of study characteristics and key findings

Study	Aims	Methodology	Participants/Cases	Country	Key Findings
Assessment of Crash Parameters
Hetz et al. (2024)	Determine ability to collect traffic-accident specific data at accident scene & inter observer variability in data collection among different professional groups.	Prospective descriptive cohort study	50	Germany	No significant difference between lay persons and health professional groups. Significant increase in layperson recognition of compartment affected and rigid object involvement after education, and non-significant increase for all other parameters except vehicle class and rollover.
Video Streaming
Idland et al. (2024)	Determine if video streaming is associated with dispatcher recognition of a need for first aid and improved quality of bystander first aid.	Prospective observational	113	Norway	Video used in 12 cases. Odds of EMS call-handler recognising need for immediate first aid > 5x higher in video group.
Linderoth et al. (2021)	Assessment of feasibility, and dispatcher perceptions & response after adding live video from bystanders in emergency calls.	Cohort Study	1020	Denmark	Call handler assessment of casualty condition changed in around half of cases using video. Video considered useful for assessing unconscious casualties.
Sonkin et al. (2022)	Assessment of the role of real-time video communication between paramedics and bystanders	Observational study	43	Israel	Video influenced paramedic decision making regarding role and equipment en route to the scene.
Taylor et al. (2024)	Feasibility randomised controlled trial with embedded process evaluation using video livestreaming during trauma incidents	Feasibility Randomised Controlled Trial	269	UK	86% of callers agreed to use video. 85% of video calls successfully established connections. Call handlers reported improvements in situational awareness.
Ter Avest et al. (2019)	To assess the acceptability and feasibility of using live video footage in HEMS dispatch	Pilot study	21	UK	Call handlers used video to assess the casualty, mechanism of injury and accident scene. 10% of connections failed.

Untrained lay-persons, when asked to identify key crash parameters from traffic accident images, performed as well as health professionals and for many variables approached the accuracy of trained traffic accident researchers. There was a positive training effect across all participant groups. While this involved only 10 lay-participants, it is an interesting proof-of-concept that accurate crash-parameter recognition is possible even amongst untrained lay-bystanders [20].

Video streaming

Smartphone ownership continues to grow globally, now accounting for 80% of the 5.8 billion unique mobile subscriptions [21]. The increasing prevalence of smartphones presents an opportunity to enhance current EMS response by using video streaming to provide real-time visual information to EMS dispatchers. There is emerging evidence for use of video streaming for CPR, but there are considerable gaps in the evidence base with regards to its use in other emergencies [22, 23].

Several studies explore the feasibility, effectiveness, and practical challenges of bystander-initiated video streaming in trauma scenarios (Table 1).

Video live streaming appears useful for call-handler assessment of trauma casualties, mechanism of injury and accident scene [24]. One cohort study showed call handler assessment of patient condition changed in around half of cases due to video live streaming and was particularly useful for assessing the unconscious patient [25]. In another study call handlers reported improvements in situational awareness and confidence in decision making [26]. Recognition of immediate first aid requirements by EMS dispatchers also appears to increase with the use of video [27]. Video may also be useful for EMS responders en route to the casualty. Paramedics reported video influenced decision making regarding role and equipment preparedness [28].

Studies demonstrate video streaming is feasible for use with both lay- and professional-bystanders [24], with one small RCT showing 86% of callers were agreeable to using video [26]. Cooperation with bystanders generally appears to be unchallenging, and video streaming is reviewed positively by bystanders [25]. Technical challenges exist such as establishing reliable connections, smartphone availability and language barriers; approximately 10–15% of video attempts appear to fail [25, 26].

Only one study explored psychological harm. No evidence of psychological harm to call handlers from increased exposure to incidents was identified, however due to low survey and interview response rates amongst bystanders, no conclusion regarding harm to bystanders could be made [26].

It should be noted these studies included cases of non-road injury trauma and medical illness. Furthermore all studies were conducted in high-income countries (HICs), and therefore the implications for low and middle income countries (LMICs), where smartphone prevalence is lower is unclear [21].

Accuracy of bystander triage

Existing triage tools

Multiple studies sought to evaluate bystander triage accuracy using established triage tools developed for use by EMS in mass-casualty incidents (MCIs) [29–33] (Table 2). Only one study sought to evaluate accuracy of layperson triage and this was also the only study to specifically evaluate triage for road injuries [29]. All other studies evaluated professional bystanders. In all of the studies, participants were provided with written or verbal injury descriptions and physiological parameters; no study asked participants to assess a casualty and derive injury characteristics or vital signs.

Table 2.

Accuracy of bystander triage - summary of study characteristics and key findings

Study	Aims	Methodology	Participants	Country	Triage Tool	Key Findings
Glow et al. (2013)	Development of novel training model for mass casualty incidents	Quasi-experimental	193 - Healthcare workers, firefighters & police	USA	Simple Treatment and Rapid Triage (START)	Accuracy of triage improved post-intervention in all occupational groups. Under/Over-triage rates not stated.
Jetten et al. (2022)	Development of prehospital triage tool for mass casualty incidents for use by laypersons.	Scoping review & Triage Tool Development	N/A	Netherlands	Keep it Simple & Safe (KISS)	Not yet validated.
Kilner et al. (2005)	To assess accuracy of firearm officer triage decision making in a simulated mass casualty incident	Quasi Experimental	82 - Police Firearms Officers	UK	Triage Sieve / Paediatric Triage Tape	Under-triage improved from ~ 21–7% and over-triage improved from ~ 18%to 11.6% with use of triage tools.
Lee et al. (2015)	To assess triage accuracy amongst different professional responder groups in a paper-based simulated mass casualty incident	Prospective cohort study	464 - Paramedic, Police & Firefighter students	Canada	Sort, Assess, Lifesaving Interventions, Treatment/Transport (SALT)	Under-triage 8.5%. Over-triage 13.5%. At 3 months triage accuracy declined in all groups.
Nilsson et al. (2015)	To evaluate the effectiveness of triage cards in training for firefighters	Randomised controlled trial	86 - Firefighters	Sweden	Sort, Assess, Lifesaving Interventions, Treatment/Transport (SALT)	Under-triage improved from 18–17%, and over-triage from 23–14% with training. No significant difference in scores at 6 months compared to post-intervention scores.
Nordberg et al. (2016)	Evaluate whether bystanders with no training in triage could prioritise paper-based injured patients using a simple triage instrument	Observational study	69 - Laypersons	Sweden	Rapid Emergency Triage and Treatments System (RETTS)	52% of participants correctly triaged all 3 cases. Under-triage rate 6.3%. Over-triage rate 12.5%. 98.5% identified the most severely injured casualty.

Collectively, these studies demonstrate that both lay and professional bystanders are capable of applying simple triage tools with varying degrees of accuracy; there is a general tendency toward over-triage. Training appears to reduce triage errors. All of the assessed triage tools rely on measurable clinical variables such as heart rate or respiratory rate. It is unclear from the available evidence whether bystander-led triage can be consistently accurate enough to be clinically useful, particularly in real-world settings where injury identification and vital sign assessment may be challenging, particularly for lay and non-clinical bystanders.

Lay person triage tools

We found only one example of a triage tool developed specifically for lay persons - the Keep it Simple and Safe (KISS) tool - which has been designed to use clearly observable signs such as talking, breathing and bleeding for casualty triage [34]. Unfortunately, this tool has yet to be validated.

Training for bystanders

There are numerous studies describing and evaluating trauma training courses for lay-persons [6]; here we have focussed on those which specifically refer to triage in their curricula (Table 3). Given the high incidence of road injury these courses frequently target commercial drivers [3, 4, 35–37]. Other target groups include government officials and police officers [4, 35, 38, 39]. All included studies occurred in LMICs where motor vehicle collisions are more common, and EMS remains in its nascent stage [40].

Table 3.

Training for bystanders - summary of study characteristics and key findings

Study	Aims	Methodology	No of Participants	Participant Characteristics	Country	Key Findings
Aekka et al. (2015)	Evaluation of trauma training course for layperson first responders	Quasi-experimental	48	Taxi Drivers, Police Officers, Firefighters, Healthcare Workers	India	Sig. increase in triage competence
Delaney et al. (2018)	Evaluation of trauma training course for layperson first responders	Quasi-experimental	154	Boda-Boda Drivers	Uganda	Scene safety scores increased (37.6–59.5%)
Eisner et al. (2020)	Evaluation of Training of Trainers (TOT) approach for layperson first responder scheme	Quasi-experimental	500	Students, Taxi Drivers, Teachers, Professional Drivers	Sierra Leone	Sig. increase in scene safety scores. Significant Knowledge regression at 9 months.
Eisner et al. (2024)	Evaluation of digital hybrid TOT approach for layperson first responder scheme	Quasi-experimental	380	Transportation Providers	Nigeria	Sig. increase in median scene safety score by 43.8%. No sig. difference between ToT groups.
Hancock et al. (2020)	Evaluation of trauma training course for Layperson first responders	Quasi-Experimental with follow up cohort study	136	Taxi Drivers, NGO volunteers	Chad	Sig. increase in scene safety scores (33–59.3%)
Jayaraman et al. (2009)	Evaluation of trauma training course for Layperson first responders	Quasi-experimental with cross sectional survey	309	Police officers, Taxi Drivers, Government officials	Uganda	No evaluation of Triage
Jayaraman et al. (2009)	To assess long term effectiveness of trauma training program for layperson first responders & provision of first aid	Cross Sectional Survey	309	Police officers, Taxi Drivers, Government officials	Uganda	No evaluation of Triage
Koranda et al. (2023)	Evaluation of trauma training course for layperson first responders	Quasi-experimental	45	Police Officers	Tanzania	No evaluation of Triage
Mock et al. (2002)	Determine provision of first aid following trauma training course for layperson first responder	Cohort Study	335	Commercial Drivers	Ghana	No evaluation of Triage
Tiska et al. (2004)	Formulation of trauma training program for layperson first responders	Cohort Study	335	Commercial Drivers	Ghana	No evaluation of Triage
Vyas et al. (2016)	To assess confidence following trauma training program for layperson first responders	Cross Sectional Survey	918	Firefighters, Police officers, Taxi Drivers, Healthcare professionals	India	Sig. increase in participant confidence in Triage

The curricula for these courses appear to be derived from pre-existing trauma guidelines [4, 35], and while these courses are numerous and geographically diverse they frequently appear to be derivatives of each other therefore there is likely significant homogeneity amongst these courses [3, 36, 41]. The included studies do not share their exact curricula nor do they describe precisely how triage is taught, although frequently triage appears to be incorporated within scene management [3, 4, 36, 38, 41].

Two studies involving commercial drivers reported improvements in participant knowledge, including scene management, however this was assessed using only a 15-item questionnaire [3, 36]. A further study also reported a significant increase in triage competence scores, however this study included healthcare professionals as well as lay- and professional-bystanders; scores for individual occupational classes are not reported, and assessment methodology is unclear [35]. Several other studies included triage as a curriculum component, but evaluation was insufficient or not-reported and thus we are unable to evaluate these programmes in relation to triage teaching [4, 5, 37, 39, 42].

Two studies report the use of a Training of Trainers (ToT) approach with increased scene management scores. There were no significant differences in scores obtained between ToT groups suggesting high internal consistency of training. Knowledge regression at 9 months was reported [38, 41].

In interviews, lay responders reported using their triage skills to determine referral decisions based on health centre proximity and injury severity during subsequent casualty encounters [3]. Pre- and post-training surveys also showed increased participant confidence within the triage curriculum domain [43].

While it is evident from these studies that triage is recognised as an essential component of bystander education curricula, it is unclear how triage is being taught. There is some limited evidence to suggest bystanders are able to learn triage skills, and training increases confidence. There is also some evidence to suggest ToT models may be useful for knowledge dissemination to wider populations. Knowledge regression appears to occur, potentially necessitating repeat training. These findings should be interpreted cautiously given the lack of clarity regarding curricula and robustness of assessment methodology.

Discussion

Bystanders play an important role in the road injury chain of survival from facilitating EMS response through to provision of immediate life saving first aid [11, 44]. We believe bystanders may have additional roles in the assessment and triage of trauma casualties above and beyond established practice.

The evidence presented here suggests bystanders can augment the current triage paradigm by providing enhanced data to EMS through crash-scene assessment and video livestreaming. There is limited evidence to suggest lay-persons are as adept as healthcare professionals at assessing crash parameters. Video live streaming appears feasible and acceptable to both bystanders and call-handlers, improving situational awareness and influencing decision making. There are technical challenges to overcome, and feasibility in LMICs has not been demonstrated.

Bystanders may be able to participate actively in triage using simple triage tools. There is a tendency towards over-triage. Minimising under-triage is essential for preventing morbidity and mortality, and therefore tendency towards over-triage may be preferred, however at a system level significant over-triage risks unnecessary resource utilisation and potential delays to care in an overburdened system. A rate of 1–5% for under-triage and 25–35% have been suggested but this may vary significantly depending on method of calculation, and the definitions used in pre-hospital care versus hospital care [45].

There are a wide variety of existing bystander training programmes particularly in LMICs, many of which appear to recognise triage as a valuable skill for lay- and professional-bystanders, however there is a paucity of detail regarding the teaching of triage and concern regarding the quality of evidence [6].

From the available literature there appears to be insufficient evidence to determine differences between lay- or professional-bystander groups with regards triage accuracy, willingness to assist, or clinical and system benefits.

Several limitations should be acknowledged when interpreting these findings. The studies reviewed were highly variable in methodology, ranging from paper-based triage exercises to simulation-based training; cohort studies to RCTs. Many of these studies also include data from non-road injury trauma. Direct comparison is challenging. Furthermore there is a preponderance of small sample sizes making it difficult to assess the replicability and magnitude of interventions.

This review was limited to published literature, meaning relevant unpublished training programs or grey literature reports may not have been captured, potentially introducing publication bias. While we identified studies from both high- and low-income settings, there was a lack of data from middle-income countries, where emerging EMS systems and urbanisation may present distinct challenges for bystander triage and intervention. Finally, this review did not systematically assess the quality of included studies, so findings should be interpreted with caution.

It is also worth noting the challenge of nomenclature. There is no apparent formalised structure for describing bystanders, therefore other studies may vary from ours in their classification. It has been shown previously that there is considerable variation in the interpretation of ‘bystander-CPR’ particularly when involving volunteer responders, and professional-bystanders [46]. In our review we have categorised bystanders as lay-bystanders, i.e. members of the public; and professional-bystanders, i.e. Police, Fire & Rescue personnel, or other non-clinical professionals involved in the emergency response. We exclude those who form part of the established medical response i.e. EMTs, Paramedics, Nurses & Doctors. Classification of some groups is challenging and inexact. For instance, in the USA firefighters may be dual certified as firefighter/EMTs or firefighter/paramedics [47]. The level of first-aid training received by individuals within both the lay- and professional-bystander groups may vary considerably, and in some instances overlap.

What remains unclear is the best way to use bystanders in triage of road injury. From the evidence gathered one can begin to envisage three possibilities. One approach would be increased use of video-streaming from bystanders’ mobile devices, providing EMS call-handlers and first-responders with greater insight into the mechanism and extent of injury. Further research is needed to explore strategies to optimise connectivity, assess the clinical impact of video-assisted bystander interventions on patient outcomes, and determine the risk of psychological harm to both bystanders and call-handlers.

The second approach would be to use simple assessment and triage tools which incorporate easily observable variables which require little to no formal training, such as Ten-Second-Triage, sBATT or KISS [13, 34, 48]. These tools could be used by EMS call-handlers in collaboration with bystanders, or could even be accessible via an app. Additional work is required to determine which signs and physiological parameters bystanders are able to recognise and measure accurately, and these tools would need validating in the context of bystander triage for road injury.

The third approach would be to selectively target and train high-yield groups who are more likely to encounter road traffic incidents, such as commercial drivers and professional bystander groups (e.g. Police, Fire & Rescue). These groups may also receive training to provide immediate life saving interventions. Repeated training is likely to be required to prevent knowledge and skill regression, introducing a potentially significant training burden for trainers and trainees alike. The use of virtual or training-of-trainer courses may mitigate this burden and facilitate dissemination of knowledge to wider groups [6, 38].

Future research should prioritise three key areas. First, there is an urgent need to assess whether bystander triage and early intervention confer measurable clinical or system based benefits such as improved resource utilisation or reductions in patient morbidity & mortality. This should include an exploration of differences between lay- and professional-bystander groups. Second, further research is needed to identify which physiological parameters and injury signs can be reliably assessed by laypersons, ensuring that triage tools are both usable and clinically meaningful. Finally, the impact on bystanders from involvement in the trauma response requires greater exploration. The physical safety of bystanders, psychological impact, and willingness to intervene should be evaluated, ensuring the training and use of bystanders remains practical, ethical and sustainable.

Conclusion

There is limited evidence to demonstrate clinical or system-level benefits of bystander-led triage in the context of road injury. While bystanders appear willing and capable of applying simple triage tools, the real-world impact on patient outcomes remains unclear. Trauma training programmes can improve knowledge and skill, but their effectiveness in practice—and the durability of learning—require further evaluation. Emerging technologies, such as video live-streaming, show promise in enhancing situational awareness and triage accuracy, though technical and ethical challenges must be addressed. Future research should focus on identifying feasible, reliable approaches to bystander triage that deliver measurable improvements in patient outcomes and resource utilisation.

Supplementary Information

Below is the link to the electronic supplementary material.

Abbreviations

AMPDS

Advanced medical priority dispatch systems

CPR

Cardiopulmonary Resuscitation

EMS

Emergency Medical Services

EMT

Emergency Medical Technician

HEMS

Helicopter Emergency Medical Services

HIC

High Income Country

LMIC

Low-Middle Income Country

MCI

Mass Casualty Incident

TOT

Training of Trainers

Author contributions

TN conceived of the research questions and review design. GR and NA formulated the search parameters with contributions from TN & JGH. GR, NA & JGH screened articles for inclusion. GR was the primary author of this manuscript. All authors provided critical feedback to shape the review, analysis and writing of the manuscript. All authors have read and approved the final manuscript.

Funding

IMPACT’s Bystander workstream is supported by the Road Safety Trust. The funder had no role in the design of the study; in the collection, analysis, or interpretation of data; in the writing of the manuscript; or in the decision to submit the article for publication.

Data availability

No datasets were generated or analysed during the current study.

Declarations

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.