title: Effect size of contributory factors on adverse events: an analysis of RCA series in a teaching hospital.
abstract: BACKGROUND
  One of the most important concerns of health care systems in the world is the patient safety issues. Root Cause Analysis is a systematic process for identifying root causes and contributory factors of problems or events. The objective of this study is to review RCA reports to determine the effect size of contributory factors on adverse events through an organizational perspective.
  
  
  METHODS
  This study was conducted in a tertiary care teaching hospital in 2014. The process of root cause analysis was taken from National Patient Safety Agency framework. We calculated descriptive statistics to determine the frequency distribution of contributory factors on each adverse event.
  
  
  RESULTS
  Having the process of 16 adverse events reviewed, 38 care or service delivery problems were identified which showed that 317 contributory factors and underlying causes had led to these problems. Accordingly, the most important contributory factors included the following: Task factors (20 %), education and training factors (16 %), communication factors (14 %), and team and social factors (13 %).
  
  
  CONCLUSIONS
  RCA is an effective method of problem solving used for identifying the root causes of initial errors and finding ways to prevent the recurrences. In this study, lack of effective communication skills of nurses and other clinical staff when interacting with colleague and communicating with patients, failure to comply with health care provision standards, lack of adequate supervision on implementation of clinical guidelines and issues related to the organizational culture were the main determining factors which have been considered for implementing preventive measures with regard to the hospital specifications.
authors.affiliation: Health care management, Department of Health Economics and Management, School of Public Health, Students' Scientific Research Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Zhila
authors.initials: Z
authors.lastname: Najafpour
authors.affiliation: Shariati Hospital,Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohamadreza
authors.initials: M
authors.lastname: Jafary
authors.affiliation: Emergency Medicine research center, Shariati hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Morteza
authors.initials: M
authors.lastname: Saeedi
authors.affiliation: Digestive Diseases Research Institute (DDRI), Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Jeddian
authors.affiliation: Health services management, Endocrinology & Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Adibi
keywords: Adverse events; Contributory factors; RCA