Article Text

Download PDFPDF
Incidence and causes of critical incidents in emergency departments: a comparison and root cause analysis
  1. M Thomas1,
  2. K Mackway-Jones2
  1. 1
    Emergency Department, Hope Hospital, Salford, UK
  2. 2
    Emergency Medicine Research Group, Manchester Royal Infirmary, Manchester, UK
  1. Dr M Thomas, Emergency Department, Hope Hospital, Salford M6 8HD, UK; martin.thomas{at}


Objectives: To investigate the incidence of critical incidents in UK emergency departments (EDs) and to compare the root causes of such incidents between different EDs.

Methods: An observational study with semi-structured interviews and root cause analysis was conducted over a 12-month period. It was set in EDs in two teaching hospitals and two district general hospitals in the north-west of England. A single investigator identified critical incidents by a variety of means and conducted interviews with involved members of staff. The main outcome measures were rates of occurrence of critical incidents per 1000 new patients in each ED and root cause analysis of identified critical incidents according to a predetermined system.

Results: 443 critical incidents were identified. The rate of occurrence ranged from 11.1 to 15.9 per 1000 new patients. The most common root causes underlying these critical incidents related to organisational issues outside the EDs; internal management issues; human errors relating to knowledge or task verification and execution; and issues related to patient behaviours. By contrast, technical root causes occurred infrequently. Significant differences were shown between the EDs for three types of root cause relating to organisational issues outside the EDs and internal protocol and collective behaviour issues.

Conclusion: Critical incidents occur frequently in EDs. There are significant differences, as well as common themes, in the causes of these critical incidents between different EDs.

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


  • MT conducted the study and wrote the initial draft of the paper. KMJ conceived, designed and oversaw the study, contributed to the final draft of the paper and is the guarantor.

  • Funding: Funded by an NHS R&D grant.

  • Competing interests: None.