Field triage systems: Methodologies from the literature

doi:10.1016/j.prehos.2003.12.004

Prehospital Emergency Care

Volume 8, Issue 2, April–June 2004, Pages 130-137

https://doi.org/10.1016/j.prehos.2003.12.004 Get rights and content

Abstract

The primary goal of the Neely Conference project is to work toward defining a set of research criteria for medical necessity in emergency medical services (EMS). This paper reviews the extant literature on triage and nontransport decisions made in the field by EMS personnel, with emphasis on the methodologies that have been used to date. Two types of medical necessity standards are considered. First, there are triage criteria for determining whether a given patient requires EMS transport to the hospital, or whether an alternative might be appropriate. These triage criteria might be incorporated into protocols that field personnel could apply on scene to determine the best disposition for a given patient. Second, there are the outcome measures against which the decisions made by the field personnel are judged. In some cases, the outcome measure is the judgment of a reviewing emergency physician or nurse, while in others specific outcome measures are used to judge the performance of the criteria and the decision making of the field providers. While review of the literature shows that no “standard” set of triage criteria have been generated or validated in determining medical necessity in EMS, there are certain themes that emerge from the literature, and these themes can likely form the basis of a consensus on elements of a medical necessity criteria that need to be validated and refined. These may include (for triage criteria) vital signs, chief complaints, and physical exam findings, and (for outcome measures) hospital admission, critical events, death, and diagnosis.

Section snippets

The core literature

The first study to attempt to develop and validate formal protocols by which field personnel could assign transport options was published by Schmidt and colleagues in 2000.⁴ Because two subsequent studies have attempted to refine the methods used, this study is described in significant detail here. The study objective was to determine whether it is feasible and safe to develop a set of protocol-based triage criteria for emergency medical technicians (EMTs; at any level of training from EMT-B to

Other studies

A number of studies have examined issues that are somewhat peripheral to the concept of field triage to alternative resources, but have proposed or used triage criteria or outcome measures that could be of value to those considering this type of research.

In 2001, Cone and Wydro published a study examining whether EMT-Bs can safely determine whether ALS is needed.¹⁶ Cancellation of inbound ALS units by on-scene EMT-Bs was judged to be inappropriate if any of the following triage criteria were

Discussion and conclusions

No “standard” set of triage criteria have been generated or validated in determining medical necessity in EMS. There are certain themes that emerge from the literature, and these themes can likely form the basis of a consensus on elements of set of medical necessity criteria that need to be validated and refined. For example, many of the studies cited here use vital sign values, chief complaints, and physical examination findings, either to exclude a patient from consideration of anything other

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Cited by (19)

Clinician and Caregiver Determinations of Acuity for Children Transported by Emergency Medical Services: A Prospective Observational Study
2023, Annals of Emergency Medicine
Citation Excerpt :
The primary objective of this study was to determine the ability of each of the 4 stakeholder groups to identify low acuity pediatric patients. Our gold standard for patient acuity, to compare with stakeholder assessment, was a novel composite measure based on the results of the Neely Conference.30–33 The composite measure consisted of a patient: not having unstable vital signs, not requiring any urgent or emergency resources by the EMS or in the ED, and not having a final ED disposition of admission to the hospital or death.
Many Emergency Medical Services (EMS) agencies have developed alternative disposition processes for patients with nonemergency problems, but there is a lack of evidence demonstrating EMS clinicians can accurately determine acuity in pediatric patients. Our study objective was to determine EMS and other stakeholders' ability to identify low acuity pediatric EMS patients.
We conducted a prospective, observational study of children transported to a pediatric emergency department (ED) by EMS. Acuity was defined using a composite measure that included data from the patient’s vital signs and examination, resources used (laboratory results, radiographs, etc), and disposition. For each patient, an EMS clinician, patient caregiver, ED nurse, and ED provider completed a survey as soon as possible after the patient’s arrival at the ED. The survey asked respondents 2 questions: to state their level of agreement that a patient was low acuity and could the patient have been managed by various alternative dispositions. For each respondent group, we calculated the sensitivity, specificity, and positive and negative predictive values for low acuity versus the composite measure.
From August 2020 through September 2021, we approached 1,015 caregivers, of whom 996 (99.8%) agreed to participate and completed the survey. Survey completion varied between 78.7% and 84.1% for EMS and ED nurses and providers. The mean patient age was 7 years, 62.6% were non-Hispanic Black, and 60% were enrolled in public insurance programs. Of the 996 patient encounters, 33% were determined to be low acuity by the composite measure. The positive predictive value for EMS clinicians when identifying low acuity children was 0.60 (95% confidence intervals [CI], 0.58 to 0.67). The positive predictive value for ED nurses and providers was 0.67 (95% CI, 0.61 to 0.72) and 0.68 (95% CI, 0.63 to 0.74) respectively. The negative predictive value for EMS clinicians when identifying not low acuity children was 0.62 (95% CI, 0.58 to 0.67). The negative predictive value for ED nurses and providers was 0.72 (95% CI, 0.68 to 0.76) and 0.73 (95% CI, 0.70 to 0.77) respectively. Caregivers had the lowest positive predictive value 0.34 (95% CI, 0.30 to 0.40) but the highest negative predictive value 0.82 (95% CI, 0.79 to 0.85). The EMS clinicians, ED nurses and providers were more likely than caregivers to think that a child with a low acuity complaint could have been safely managed by alternative disposition.
All 4 groups studied had a limited ability to identify which children transported by EMS would have no emergency resource needs, and support for alternative disposition was limited. For children to be included in alternative disposition processes, novel triage tools, training, and oversight will be required to prevent undertriage.
EMS-Initiated Refusal of Transport: The Current State of Affairs
2009, Journal of Emergency Medicine
Citation Excerpt :
In 2003, “The Neely Conference: Developing Research Criteria to Define Medical Necessity in EMS” convened EMS physicians, researchers, administrators, providers, and federal agency representatives to begin development of uniform triage criteria and outcome measures that could be used in studies examining, among others, pre-hospital triage and need for emergent transport (9). This conference provided at least some consensus on critical questions that need to be answered in order for EMS researchers to further progress in this critical area (10). We look forward to using these recommendations as well as the EMS-initiated refusal of transport protocols from already-established programs to further our goal of developing and prospectively validating an effective pre-hospital triage tool.
The objectives of this study were 1) to determine the number and characteristics of emergency medical services (EMS) agencies within the 200 largest US cities that sanction EMS-initiated refusal of transport; and 2) to determine the extent of no-cost alternative transport mechanisms among those agencies that allow EMS-initiated refusal of transport. EMS agencies located within the 200 largest US cities were contacted via telephone and surveyed as to whether their agency sanctioned EMS-initiated refusal of transport (EMS-IROT). Agencies with a policy were further questioned regarding its components and usage patterns. The telephone survey contacted 100% (200) of the target population. Currently, 7.0% (14) of EMS agencies have EMS-IROT protocols, with 64% (9) of those requiring direct medical oversight. Five (2.5%) of the 200 agencies sanctioned EMS-IROT without requiring online medical approval. Average annual call volume of the five agencies not requiring direct medical oversight was 70,800; their EMS-IROT protocols have been in existence a mean of 19.8 years. None of these agencies had a no-cost alternative transport mechanism. Three (1.5%) agencies terminated EMS-IROT protocols in the past. EMS-initiated refusal of transport continues to be a rare entity among US EMS agencies. Those that do not require direct medical oversight tend to have well-established programs, though no agency offered a formal no-cost alternative transport mechanism.
Challenges and Opportunities to Engaging Emergency Medical Service Providers in Substance Use Research: A Qualitative Study
2017, Prehospital and Disaster Medicine
A modified simple triage and rapid treatment algorithm from the New York City (USA) fire department
2015, Prehospital and Disaster Medicine
Reasons why patients choose an ambulance and willingness to consider alternatives
2006, Academic Emergency Medicine
Citation Excerpt :
Overcrowded EDs and busy EMS systems have motivated previous studies that have attempted to evaluate the safety and cost-efficiency of alternatives to ambulance transport. Those studies have used different criteria for determining the safety of field triage.15 To the best of the authors' knowledge, they have not considered whether or not patients would be willing to consider alternatives.
To test a hypothesis that patients would accept alternatives to transport to an emergency department (ED) by ambulance and to evaluate factors related to patient willingness to consider alternatives. Concerns about resource utilization have prompted emergency medical services (EMS) systems to explore alternatives to ambulance transport to an ED, but studies have evaluated the safety of alternatives, not patient preferences.
Trained research assistants surveyed patients transported by ambulance to a university ED. Interfacility transfers, trauma patients, and critically ill patients were excluded. The primary outcome was willingness to accept one of several presented alternatives to ambulance transport to the ED for that visit. Demographic and clinical factors were evaluated for association with willingness to consider alternatives. Relative risks (RR) and 95% confidence intervals (95% CI) were determined by using Mantel-Haenszel stratified methods.
Three hundred fifteen subjects completed the survey. Two hundred forty-seven (78.4%) were willing to consider at least one alternative. One hundred ninety-four (61.6%) were willing to consider transportation by car, and 177 (56.2%) were willing to consider transportation by taxi. Factors associated with willingness to consider alternatives included the following: age 18–65 years (RR, 1.25; 95% CI = 1.03 to 1.49), being unemployed (RR, 1.08; 95% CI = 1.08 to 1.33), use of the ED for routine care (RR, 1.25; 95% CI = 1.17 to 1.35), and not being admitted to the hospital (RR, 1.19; 95% CI = 1.04 to 1.40). Race, gender, health insurance status, and EMS interventions en route were not associated with willingness to consider transportation alternatives.
Many patients transported by ambulance to an ED would have considered an alternative, if one were offered.
Mobile integrated health and community paramedicine
2021, Emergency Medical Services: Clinical Practice and Systems Oversight: Third Edition

View all citing articles on Scopus

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Presented at The Neely Conference: Developing Research Criteria to Define Medical Necessity in EMS, National Association of EMS Physicians Annual Meeting, Panama City, Florida, January 15, 2003.

Financial support for the Neely Conference project was received from the National Association of EMS Physicians, the National Highway Traffic Safety Administration, U.S. Department of Transportation, and the Neely EMS Research Fund.

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Special contributionField triage systems: Methodologies from the literature☆

Abstract

Section snippets

The core literature

Other studies

Discussion and conclusions

Prehosp Emerg Care

Ann Emerg Med

Ann Emerg Med

Prehosp Emerg Care

Prehosp Emerg Care

Prehosp Emerg Care

Prehosp Emerg Care

Ann Emerg Med

Alternate ambulance transportation destination. National Association of EMS Physicians/American College of Emergency Physicians Joint Position Paper

Prehosp Emerg Care

National Association of EMS Physicians/American College of Emergency Physicians Joint Position Paper

Prehosp Emerg Care

Appropriate emergency medical services transport

Acad Emerg Med

Evaluation of protocols allowing emergency medical technicians to determine need for treatment and transport

Acad Emerg Med

Special contribution
Field triage systems: Methodologies from the literature☆