Materials and Methods
Data source This study was a retrospective analysis to review all lawsuit cases of colon perforation during colonoscopy using the Court Records of the Republic of Korea ruled from January 2005 to December 2015. We used the keyword of ’colonoscopy’ in the ‘Written Judgment Public Reading System’ provided by the Supreme Court. The courts provided us with the copies of the written judgements deleted personal information. Among the written judgments we collected, the following types of cases were excluded; 1) non-colonoscopy cases, 2) non-perforation cases, 3) non-colon perforation, or 4) cases with insufficient clinical information. When an appeal was made on a case, only the final judgment was included in this study.Study designThe written judgments were reviewed and assessed by two researchers (HM Oh and SH Shin), independently. If the assessments of the two researchers were divergent, they tried to reach common ground through discussion, and if an agreement was not reached, a third researcher (S Choi) additionally analyzed the contents till an agreement was reached. Judicial and clinical information were collected. The judicial information includes type of defendant, the process of lawsuit, the trial outcome, the plaintiff’s claim, the claimed amount, and the payment awarded. For the claimed amount and awarded compensation, 1 US Dollar (USD) was converted to 1,165 Korean won based on the average exchange rate in 2019. Clinical information such as the patient’s age and sex, indication of colonoscopy, perforation cause and location, the type of surgical treatment, and final outcomes were also collected. In addition, information pertaining to the type of recognition of colon perforation, interventions for perforation, and time elapsed from procedure to diagnosis of perforation were also collected. The diagnosis time point for the colon perforation was defined as the point at which perforation was confirmed with a radiologic examination or a clinical suspicion by a doctor. We divided the patients into three groups according to the degree of contamination in the abdominal cavity, the occurrence of shock, and organ damage using the classification of Flint14. Three groups were defined as follows: grade 1 - cases of simple surgery, such as a suture, grade 2 - cases in which the patient had temporary colostomy, and grade 3 - cases with cardiopulmonary resuscitation or deep shock events.Statistical analysisData normality was tested with the Shapiro-Wilk test. To compare the three groups based on Flint’s classification, the Kruskal-Wallis tests with Bonferroni’s correction for multiplicity were performed and considered statistically significant when p < 0.05. All statistical analyses were conducted using Microsoft Excel 2013 (Redmond, WA, USA) and IBM SPSS Statistics 25 for windows (Chicago, IL, USA).Ethics statementThis retrospective study was approved by the Institutional Review Board in Yonsei University Health System (No. Y-2020-0097) and informed consent was waived.