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Is Overtriage Associated With Increased Mortality? Insights From a Simulation Model of Mass Casualty Trauma Care


Purpose: To examine the relationship between overtriage and critical mortality after a mass casualty incident (MCI) using a simulation model of trauma system response.

Methods: We created a discrete event simulation model of trauma system management of MCIs involving individual patient triage and treatment. Model variables include triage performance, treatment capability, treatment time, and time-dependent mortality of critically injured patients. We model triage as a variable selection process applied to a hypothetical population of critically and noncritically injured patients. Treatment capability is represented by staffed emergency department trauma bays with associated staffed operating rooms that are recycled after each use. We estimated critical and noncritical patient treatment times and time-dependent mortality rates from the trauma literature.

Results: In this simulation model, overtriage, the proportion of noncritical patients among all of those labeled as critical, has a positive, negative, or variable association with critical mortality depending on its etiology (ie, related to changes in triage sensitivity or to changes in the prevalence and total number of critical patients). In all of the modeled scenarios, the ratio of critical patients to treatment capability has a greater impact on critical mortality than overtriage level or time-dependent mortality assumption.

Conclusions: Increasing overtriage may have positive, negative, or mixed effects on critical mortality in this trauma system simulation model. These results, which contrast with prior analyses describing a positive linear relationship between overtriage and mortality, highlight the need for alternative metrics to describe trauma system response after MCIs. We explore using the relative number of critical patients to available and staffed treatment units, or the critical surge to capability ratio, which exhibits a consistent and nonlinear association with critical mortality in this model. (Disaster Med Public Health Preparedness. 2007;1(Suppl 1):S14–S24)

Corresponding author
Correspondence and reprint requests to Nathaniel Hupert, MD, MPH, Assistant Professor of Public Health and Medicine, Weill Medical College of Cornell University, 411 E 69th St, New York, NY 10021(e-mail:
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1.Hardern RD.Critical appraisal of papers describing triage systems. Acad Emerg Med. 1999;6:11661171.
2.Hoey BA, Schwab CW.Level I center triage and mass casualties. Clin Orthop Relat Res. 2004;422:2329.
3.Kluger Y, Mayo A, Soffer D, Aladgem D, Halperin P.Functions and principles in the management of bombing mass casualty incidents: lessons learned at the Tel-Aviv Souraski Medical Center. Eur J Emerg Med. 2004;11:329334. Boer J, Debacker M.A more rational approach to medical disaster management applied retrospectively to the Enschede fireworks disaster, 13 May 2000. Eur J Emerg Med. 2003;10:117123.
5.Lerner EB, Moscati RM.The golden hour: scientific fact or medical “urban legend”? Acad Emerg Med. 2001;8:758760.
6.Frykberg ER.Medical management of disasters and mass casualties from terrorist bombings: how can we cope? J Trauma. 2002;53:201212.
7. American College of Surgeons Committee on Trauma. Resources for the Optimal Care of the Injured Patient. 1999 American College of Surgeons Web site. Accessed August 7, 2007.
8.Hirshberg A.Multiple casualty incidents: lessons from the front line. Ann Surg. 2004;239:322324.
9.Severance HW.Mass-casualty victim “surge” management. Preparing for bombings and blast-related injuries with possibility of hazardous materials exposure. NC Med J. 2002;63:242246.
10.Rodoplu U, Arnold JL, Yucel T, Tokyay R, Ersoy G, Cetiner S.Impact of the terrorist bombings of the Hong Kong Shanghai Bank Corporation headquarters and the British Consulate on two hospitals in Istanbul, Turkey, in November 2003. J Trauma. 2005;59:195201.
11.Aylwin CJ, Konig TC, Brennan NW, et alReduction in critical mortality in urban mass casualty incidents: analysis of triage, surge, and resource use after the London bombings on July 7, 2005. Lancet. 2006;368 955422192225.
12.Cone DC, MacMillan DS.Mass-casualty triage systems: a hint of science. Acad Emerg Med. 2005;12:739741.
13.Hirshberg A, Stein M, Walden R.Surgical resource utilization in urban terrorist bombing: a computer simulation. J Trauma. 1999;47:545550.
14.Sacco WJ, Navin DM, Fiedler KE 2nd Waddell RK, Long WB, Buckman RF JrPrecise formulation and evidence-based application of resource-constrained triage. Acad Emerg Med. 2005;12:759770.
15.Stevenson MD, Oakley PA, Beard SM, Brennan A, Cook AL.Triaging patients with serious head injury: results of a simulation evaluating strategies to bypass hospitals without neurosurgical facilities. Injury. 2001;32:267274.
16.Sampalis JS, Denis R, Lavoie A, et alTrauma care regionalization: a process-outcome evaluation. J Trauma. 1999;46:565581.
17.Cook L.The World Trade Center attack. The paramedic response: an insider's view. Crit Care. 2001;5:301303.
18.Cushman JG, Pachter HL, Beaton HL.Two New York City hospitals' surgical response to the September 11, 2001, terrorist attack in New York City. J Trauma. 2003;54:147155.
19.Deshpande AA, Mehta S, Kshirsagar NA.Hospital management of Mumbai train blast victims. Lancet. 2007;369 9562639640.
20.Auf der Heide E.The importance of evidence-based disaster planning. Ann Emerg Med. 2006;47:3449.
21.McNeil BJ, Weber E, Harrison D, Hellman S.Use of signal detection theory in examining the results of a contrast examination: a case study using the lymphangiogram. Radiology. 1977;123:613617.
22.Garner A, Lee A, Harrison K, Schultz CH.Comparative analysis of multiple-casualty incident triage algorithms. Ann Emerg Med. 2001;38:541548.
23.Hirshberg A, Scott BG, Granchi T, Wall MJ Jr, Mattox KL, Stein M.How does casualty load affect trauma care in urban bombing incidents? A quantitative analysis. J Trauma. 2005;58:686695.
24.Avitzour M, Libergal M, Assaf J, et alA multicasualty event: out-of-hospital and in-hospital organizational aspects. Acad Emerg Med. 2004;11:11021104.
25.Frykberg ER.Principles of mass casualty management following terrorist disasters. Ann Surg. 2004;239:319321.
26.Einav S, Feigenberg Z, Weissman C, et alEvacuation priorities in mass casualty terror-related events: implications for contingency planning. Ann Surg. 2004;239:304310.
27.Segell GM.Terrorism: London public transport–July 7, 2005. Defence Security Anal. 2006;22:4559.
28.Liang NJ, Shih YT, Shih FY, et alDisaster epidemiology and medical response in the Chi-Chi earthquake in Taiwan. Ann Emerg Med. 2001;38:549555.
29.Connelly LG, Bair AE.Discrete event simulation of emergency department activity: a platform for system-level operations research. Acad Emerg Med. 2004;11:1177–85.
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Disaster Medicine and Public Health Preparedness
  • ISSN: 1935-7893
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