Study on the influence of assistant experience on the quality of colonoscopy A pilot single-center study

Background and objective: Colonoscopy is the most important method for the diagnosis and treatment of intestinal diseases, and there are many factors affecting the quality of examination. Although the assistant is one of the factors influencing the quality of colonoscopy, there are few studies on the effect of different assistants with different experiences on the quality of colonoscopy. Therefore, the study was aimed to research the correlation between different assistants with different experiences and the quality of water-injection colonoscopy. Method: In this study, a single-center randomized controlled trial was conducted to analyze the key quality indicators (the rate to arrive cecum, time to arrive cecum, total operation time, detection rate of polyps, detection rate of adenoma, pain score, operation satisfaction, and the pressure on abdomen) of patients who underwent water-injection colonoscopy under non-sedation from January 2018 to June 2018 in the center. Patients were randomly assigned to different assistant groups based on the actual working period of 6 months (0 similar to 6 months inexperienced assistant group and assistant group with more than 6 months of experience). Through fitting the bivariate and multivariate logistic regression models, the differences between the two groups and the effects on the key quality indicators of colon examination were analyzed. Results: A total of 331 patients who were eligible for non-sedation colonoscopy were randomly assigned to the experienced assistant group (n=179) and the inexperienced assistant group (n=152). Among them, 103 cases of polyp and 70 cases of adenoma were detected. The rate to arrive cecum, polyp detection rate and adenoma detection rate were compared between the two groups during operation (P>0.05). However, there were significant differences in the time to arrive cecum, patients' satisfaction with operation, pain score and abdominal pressure (P<.05). In the inexperienced assistant group, 20% of the operation time was one standard deviation higher than the mean value, while the experienced assistant group was 12% (339 s vs 405s, OR 0.541, 95% 0.295-0.990). Compared with the inexperienced assistant group, patients in the experienced assistant group had higher operational satisfaction (98.32% vs 92.11%, OR 0.199, 95% 0.055-0.718) and lower pain score (0.3 vs 0.49, OR 1.993, 95% 1.52-3.775). All relations remained unchanged after adjusting for potential confounders. Conclusion: The assistant is a key factor in the quality of colonoscopy, especially in the case of non-sedating colonoscopy. The experience of the assistant is related to the time to arrive cecum, the degree of pain and the overall satisfaction of patient with the operation. The assistant should be subject to the quality supervision of the endoscopic inspector.Proof of human Clinical Trial Registration: The institutional review board of Fifth Affiliated Hospital of Wenzhou Medical College, Zhejiang Province, China approved the study.