Effect of Emergency Department Crowding on Patient Mortality: A Systematic Review

Document Type : Systematic Review


Trauma Research Center, Clinical Sciences Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.



Introduction: Emergency department (ED) overcrowding may damage patient outcomes in various settings. This systematic review investigated the association between ED crowding and patient mortality.
Methods: A search of three electronic databases namely Medline, EMBASE, and Web of Science websites was done to identify all original English language published studies concerning mortalities caused by ED crowding between January 1999 and January 2019.
Results: A total of 45 studies were included in the full-text review. After excluding 17 studies because of poor quality, 28 articles were included in the final review. Twenty articles reported a direct association between ED crowding and emergency patient mortality. With the increase in ED overcrowding, mortality also increased. Nevertheless, eight of the studies reported no association between ED crowding and mortality.
Conclusion: ED overcrowding significantly increased patient mortality regardless of the amount of ED overcrowding and type of diseases in most studies were assessed in this study. Additional studies are required to comprehensively assess the relationship between ED overcrowding and patients’ mortality.


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