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Effect of the World Health Organization Checklist on Patient Outcomes: A Stepped Wedge Cluster Randomized Controlled Trial

Haugen, Arvid Steinar MSc*,†; Søfteland, Eirik MD, PhD*; Almeland, Stian K. MD; Sevdalis, Nick PhD§; Vonen, Barthold MD, PhD; Eide, Geir E. PhD‖,**; Nortvedt, Monica W. PhD††; Harthug, Stig MD, PhD‡‡,†

doi: 10.1097/SLA.0000000000000716

Objectives: We hypothesized reduction of 30 days' in-hospital morbidity, mortality, and length of stay postimplementation of the World Health Organization's Surgical Safety Checklist (SSC).

Background: Reductions of morbidity and mortality have been reported after SSC implementation in pre-/postdesigned studies without controls. Here, we report a randomized controlled trial of the SSC.

Methods: A stepped wedge cluster randomized controlled trial was conducted in 2 hospitals. We examined effects on in-hospital complications registered by International Classification of Diseases, Tenth Revision codes, length of stay, and mortality. The SSC intervention was sequentially rolled out in a random order until all 5 clusters—cardiothoracic, neurosurgery, orthopedic, general, and urologic surgery had received the Checklist. Data were prospectively recorded in control and intervention stages during a 10-month period in 2009–2010.

Results: A total of 2212 control procedures were compared with 2263 SCC procedures. The complication rates decreased from 19.9% to 11.5% (P < 0.001), with absolute risk reduction 8.4 (95% confidence interval, 6.3–10.5) from the control to the SSC stages. Adjusted for possible confounding factors, the SSC effect on complications remained significant with odds ratio 1.95 (95% confidence interval, 1.59–2.40). Mean length of stay decreased by 0.8 days with SCC utilization (95% confidence interval, 0.11–1.43). In-hospital mortality decreased significantly from 1.9% to 0.2% in 1 of the 2 hospitals post-SSC implementation, but the overall reduction (1.6%–1.0%) across hospitals was not significant.

Conclusions: Implementation of the WHO SSC was associated with robust reduction in morbidity and length of in-hospital stay and some reduction in mortality.

This quantitative, systematic study used Healthcare Failure Mode Effects Analysis to identify risks in the surgical escalation of care process. Participants identified communication, staffing, and hierarchical failures as root causes of a failure to escalate. Targeted interventions based on escalation protocols, educational sessions, and staff recruitment should improve patient safety.

*Department of Anesthesia and Intensive Care, Haukeland University Hospital, Bergen, Norway

Department of Clinical Science, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway

Department of Surgery, Førde Central Hospital, Førde, Norway

§Centre for Patient Safety and Service Quality at the Department of Surgery and Cancer, Imperial College, London, United Kingdom

Department of Surgery, Nordland Hospital, Bodø, Norway

Centre for Clinical Research, Haukeland University Hospital, Bergen, Norway

**Department of Global Public Health and Primary Care, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway

††Centre for Evidence Based Practice, Bergen University College, Bergen, Norway

‡‡Department of Research and Development, Haukeland University Hospital, Bergen, Norway.

Reprints: Arvid Steinar Haugen, MSc, Department of Anesthesia and Intensive Care, Haukeland University Hospital, Jonas Liesvei 65, N-5021 Bergen, Norway. E-mail:

Disclosure: This study received departmental support. A.S.H. was granted by the Western Regional Norwegian Health Authority (grant numbers 911635 and 911510). N.S. is affiliated with the Imperial Center for Patient Safety and Service Quality, which is funded by the National Institute for Health Research, UK. The funders had no role in the design, conduct, or analysis of this study. The authors report no conflicts of interest.

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