ACADEMIC EMERGENCY MEDICINE 2012; 19:106–109 © 2011 by the Society for Academic Emergency Medicine
Objectives: Patient acuity triage systems can play an important role in supporting patient safety and emergency department (ED) operations. In 2003, the boards of the American College of Emergency Physicians (ACEP) and the Emergency Nurses Association (ENA) approved a joint statement calling for hospitals to adopt a reliable, valid, five-level triage scale such as the Emergency Severity Index (ESI). Still, there appears to be considerable variation in use of triage acuity systems in the United States, with many hospitals using three- and four-level systems that have not been validated. The purpose of this effort was to measure the use of various triage acuity systems in U.S. hospitals.
Methods: The authors conducted a cross-sectional analysis of secondary data. Data were obtained from the 2009 American Hospital Association (AHA) Annual Survey—an intensive questionnaire mailed to all U.S. general medical and surgical hospitals. In 2009, a question was added to the survey about hospitals’ use of triage systems in EDs. Descriptive statistics were used to explore various triage acuity systems used by different types of hospitals.
Results: Of the 4,897 hospitals surveyed, 82% responded, and 62% (3,024 hospitals) provided information on their ED triage system. The 2009 data revealed that the most commonly used triage system types were the five-level ESI (56.9% of responding hospitals) and three-level triage systems (25.2%). More than 70% of large hospitals and teaching hospitals use the ESI, and the unvalidated three-level systems were more common in small hospitals, public hospitals, nonteaching hospitals, and hospitals in the Midwest. The majority (72.1%) of all ED patient visits to hospitals in our sample were assessed using ESI; only 13.1% of visits were assessed using a three-level system.
Conclusions: Among our sample of more than 3,000 hospitals, the ESI was the most commonly used triage system, and more patients were triaged using the ESI than any other triage acuity system. Still, there is an opportunity to further promote the adoption of validated, reliable triage systems.
The purpose of emergency department (ED) triage is to sort incoming patients, prioritizing those needing immediate care from others who can wait. Triage is an important part of an organization’s efforts to assure patient safety, particularly in crowded EDs.1 Failure to triage patients appropriately may leave very sick patients at risk for deterioration while waiting. Triage also plays a key role in ED operations, making sure that scarce resources are directed to patients with the greatest need and facilitating accurate description of ED case mix. Widespread adoption and use of a common, reliable triage system is essential for making comparisons across hospitals (e.g., waiting times), facilitating numerous research activities (e.g., providing data to investigate the link between patient acuity and ED crowding2,3), and permitting benchmarking between EDs.
Traditionally, hospitals have used three-level triage acuity systems (e.g., emergent, urgent, nonurgent). A 2001 survey of 1,380 hospitals conducted by the Emergency Nurses Association (ENA) showed that 69% used a three-level system, 12% used a four-level scale, and 3% used a five-level scale.4 Since then, several studies have reported that five-level systems, such as the Emergency Severity Index (ESI) and the Canadian Triage Acuity System (CTAS), are more reliable (i.e., consistent) than three-level systems.2,5,6 Five-level systems have also been validated through research demonstrating an association between triage level and resource use, hospitalization, and mortality.2,5,6 As a result, in 2003, the Boards of the American College of Emergency Physicians (ACEP) and ENA approved a joint position statement supporting hospitals’ adoption of a reliable, valid five-level triage scale.7 Additionally, the Agency for Healthcare Research and Quality (AHRQ) devoted resources to fund the development and dissemination of ESI training materials.1,8
Despite these efforts, there is currently no universal triage acuity system in the United States, and anecdotally there appears to be considerable variation in use of triage systems. The purpose of this effort was to identify the use of various triage systems in U.S. hospitals and identify characteristics of those hospitals.
Study Design and Population
This was a cross-sectional analysis of secondary data. This research was deemed exempt from full review and informed consent requirements by the institutional review board of the Health Research and Educational Trust, an affiliate of the American Hospital Association (AHA).
Survey Content and Administration
Data were obtained from the 2009 AHA Annual Survey, which was fielded from January to May 2010. The survey, conducted annually since 1946, provides a cross-sectional view of the hospital industry, collecting information on hospital size, ownership, geographic location, services, teaching status, and number of patient visits. The survey is mailed to all hospital chief executive officers (CEOs) in the United States (i.e., AHA members and nonmembers), and they are instructed to circulate the survey to the individuals most appropriate to complete the different sections.
In 2009, the following question was added: “Which of the following best describes the type of triage system your ED uses on a daily basis to determine which patients can wait to be seen and which need to be seen immediately.” Reponses options included: three-level system; four-level system; five-level ESI; five-level system, other (please specify); and do not know. Fifty-five respondents who marked “other” indicated in the free text that they use a five-level triage system other than ESI (e.g., CTAS) and their responses were recoded as “five-level system.” We also created two additional categories based on the free text responses: two-level system and no triage system.
We used descriptive statistics to explore the use of various triage systems by different hospital characteristics (size, ownership, teaching/nonteaching, annual ED visits, and region of the United States). We used data on number of ED visits from the AHA annual survey to calculate the percentage of ED patients served by various triage systems. Analyses were performed using Stata version 10.0 (StataCorp, College Station, TX).
In 2009, the survey was mailed to CEOs from 4,897 general medical and surgical hospitals, and 4,009 (82%) responded. We limited our analysis to the 3,024 hospitals that provided information on their triage systems (62% of all hospitals). Compared to all general medical and surgical hospitals in the United States, the hospitals included in our analysis were more likely to be large hospitals, teaching hospitals, and private not-for-profit hospitals.
The most commonly used triage system types among respondents were five-level ESI (56.9%) and three-level triage systems (25.2%; Table 1). There were large differences in use of ESI by hospital characteristics. More than 70% of large hospitals and teaching hospitals reported using ESI. However, among responding small hospitals, three-level systems were the most commonly used triage systems. Nonfederal public hospitals were just as likely to use three-level triage systems as ESI. When examining data on a patient visit level at the responding hospitals, 72.1% of ED visits were assessed using ESI, compared to only 13.1% assessed using a three-level system.
|Characteristic (n)||No Triage System||Two-level System||Three-level System||Four-level System||Five-level ESI||Other Five-level System||Other Triage System|
|All hospitals (N = 3,024)||0.7||0.3||25.2||9.6||56.9||6.3||1.0|
|All patients (N = 95,434,081)||0.1||0.0||13.1||6.5||72.1||7.6||0.1|
|Small hospitals (1,325)||1.5||0.6||40.6||13.6||37.3||4.8||1.6|
|Medium hospitals (1,055)||0.1||0.1||15.8||6.5||69.6||7.6||0.3|
|Large hospitals (644)||0.0||0.0||9.0||6.4||76.6||7.3||0.8|
|Nonfederal public hospitals (669)||1.9||0.4||39.3||14.5||39.2||3.7||0.9|
|Federal public hospitals (51)||0.0||0.0||17.6||11.8||66.7||3.9||0.0|
|Private not-for-profit hospitals (1,933)||0.4||0.3||21.2||7.9||62.5||6.7||1.1|
|Private for-profit hospitals (371)||0.3||0.0||22.1||9.4||58.5||9.4||0.3|
|Teaching hospitals (860)||0.0||0.0||12.9||7.7||72.9||5.8||0.7|
|Nonteaching hospitals (2,164)||1.0||0.4||30.1||10.4||50.6||6.5||1.1|
|Less than 1,000 ED Visits/yr (93)||6.5||2.2||60.2||19.4||7.5||1.0||3.2|
|1,000–24,999 ED visits/yr (1,481)||1.0||0.5||37.1||13.1||42.0||5.2||1.2|
|25,000–49,999 ED visits/yr (805)||0.1||0.0||12.8||5.1||74.5||7.1||0.4|
|50,000–74,999 ED visits/yr (413)||0.0||0.0||9.7||4.4||76.0||9.0||1.0|
|75,000–99,000 ED visits/yr (140)||0.0||0.0||5.0||9.3||75.7||9.3||0.7|
|100,000 or more ED visits/yr (92)||0.0||0.0||8.8||6.5||78.3||6.6||0.0|
We report the most recent data of triage system use by EDs throughout the United States, since the recommendation from the ACEP and ENA boards of directors in 2005 that hospitals use a reliable, validated five-level triage system.2,7 The recommendation was informed by evidence that ESI and other five-level triage systems were superior to traditional three- and four-level systems. Use of reliable, valid five-level triage systems has several benefits. First, it provides a universal language that emergency physicians and nurses can use to recognize the acuity of all patients, including those in the waiting room and new patients placed in the treatment area. Rapid, accurate triage of patients assures that ED care givers make safe decisions about who needs immediate treatment and who can wait. Additionally, in an era of ED overcrowding, accurate patient triage supports efficient allocation of limited ED resources. Also, widespread adoption of a reliable and valid triage system permits case mix comparisons within and between hospitals.
Our results show that ESI has become widely adopted, but important differences in hospital characteristics were found by type of triage system used, particularly related to hospital size. Smaller hospitals and hospitals with <25,000 visits per year reported less use of ESI and more use of other, nonvalidated triage systems. This may be explained by two factors. First, smaller hospitals and those with fewer visits may not experience waits for physician evaluation and may not perceive a need for a formalized triage system. However, in the absence of reliable triage data, these hospitals may lack the ability to accurately estimate their case mix. Other measures of case mix, such as the percentage of patients admitted to the hospital, may underestimate patient acuity. For example, ESI Level 2 patients require urgent evaluation in the ED, but are often discharged home.
Second, small hospitals may be reluctant to adopt ESI due to limited resources to train nurses. However, several no- or low-cost training options, including a Web-based training program, are now available.1,8 A formal evaluation of the ESI training manual was conducted, and among those who requested the materials, use of ESI and satisfaction with it was high.9 Respondents reported believing ESI was more accurate than other triage tools and reduced the subjectivity of the triage process.
Our data show widespread adoption of ESI at large hospitals. This finding is important because large hospitals are more likely to experience crowding, and use of ESI is a functional requirement for the adoption of several patient flow improvement strategies (e.g., qTRACK, physician directed queuing). Also, the widespread use of ESI could support research experimentation and benchmarking across hospitals.
There are three limitations of the survey that deserve mention. First, the survey questions and terminology about triage system use have not been validated by previous research. Second, we do not have information on who actually completed the survey at each hospital. The survey contains questions about the full range of hospital services, and it is possible that some respondents were not familiar with their facilities’ triage systems. Third, our response rate was 62%, and our estimates of ESI use may be overstated because large hospitals were overrepresented.
The Emergency Severity Index was the most commonly used triage system among our responding hospitals, and most ED patients were triaged using the Emergency Severity Index. Still, there are differences in triage systems used by hospitals with various characteristics. The opportunity for increased adoption of the Emergency Severity Index or other validated, reliable triage systems, as recommended by the American College of Emergency Physicians and the Emergency Nurses Association, is clear. Our data provide some information regarding where those efforts should be targeted.
The authors thank Dr. James Adams for his thoughtful comments on a draft of the manuscript.