Background This study aimed to develop an artificial intelligence (AI)-based system for measuring fold examination quality (FEQ) of colonoscopic withdrawal technique. We also examined the relationship between the system’s evaluation of FEQ and FEQ scores from experts, and adenoma detection rate (ADR) and withdrawal time of colonoscopists, and evaluated the system’s ability to improve FEQ during colonoscopy. Methods First, we developed an AI-based system for measuring FEQ. Next, 103 consecutive colonoscopies performed by 11 colonoscopists were collected for evaluation. Three experts graded FEQ of each colonoscopy, after which the recorded colonoscopies were evaluated by the system. We further assessed the system by correlating its evaluation of FEQ against expert scoring, historical ADR, and withdrawal time of each colonoscopist. We also conducted a prospective observational study to evaluate the systemʼs performance in enhancing fold examination. Results The system’s evaluations of FEQ of each endoscopist were significantly correlated with expertsʼ scores (r = 0.871, P < 0.001), historical ADR (r = 0.852, P = 0.001), and withdrawal time (r = 0.727, P = 0.01). For colonoscopies performed by colonoscopists with previously low ADRs (< 25 %), AI assistance significantly improved the FEQ, evaluated by both the AI system (0.29 [interquartile range (IQR) 0.27–0.30] vs. 0.23 [0.17–0.26]) and experts (14.00 [14.00–15.00] vs. 11.67 [10.00–13.33]) (both P < 0.001). Conclusion The system’s evaluation of FEQ was strongly correlated with FEQ scores from experts, historical ADR, and withdrawal time of each colonoscopist. The system has the potential to enhance FEQ. ^* Co-first authors Received: 03 August 2021 Accepted: 10 February 2022 Article published online: 07 April 2022 © 2022. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/) Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany

The aim of the present study was to conduct a meta‑analysis for elucidating the effects of antibiotic prophylaxis on infection, rebleeding and mortality in patients who underwent endoscopic therapy for variceal hemorrhage. Articles on antibiotic prophylaxis and on‑demand antibiotic administration following endoscopic therapy for acute variceal bleeding were searched on PubMed, Embase and Cochrane Library between January 1959 and February 2024, to elucidate whether the use of prophylactic antibiotics was necessary. The quality of randomized controlled trials (RCTs) was assessed using the Cochrane risk‑of‑bias assessment tool and RevMan software version 5.4.1 was used for meta‑analysis of the data. The current meta‑analysis included four RCTs and 322 patients with acute variceal bleeding who underwent endoscopic therapy. All included studies were of high quality according to the Cochrane risk‑of‑bias assessment tool. According to the results of the meta‑analysis, the incidence of infection in the prophylactic antibiotic group was significantly lower than that in the on‑demand group [odds ratio (OR), 0.31; 95% confidence interval (CI), 0.13‑0.74; P=0.009]. The prophylactic antibiotic group also exhibited a lower incidence of rebleeding compared with that of the on‑demand group (OR, 0.37; 95% CI, 0.19‑0.72; P=0.003). No significant differences were noted in the incidence of mortality between the two groups (OR, 0.92; 95% CI, 0.45‑1.92; P=0.83). In conclusion, the data indicated that antibiotic prophylaxis is recommended to be used in patients who have undergone endoscopic therapy for variceal hemorrhage.