BackgroundAccurately diagnosing gallbladder polyps (GBPs) is important to avoid misdiagnosis and overtreatment. AimsTo evaluate the efficacy of a deep learning model and the accuracy of a computer-aided diagnosis by physicians for diagnosing GBPs. MethodsThis retrospective cohort study was conducted from January 2006 to September 2021, and 3,754 images from 263 patients were analyzed. The outcome of this study was the efficacy of the developed deep learning model in discriminating neoplastic GBPs (NGBPs) from non-NGBPs and to evaluate the accuracy of a computer-aided diagnosis with that made by physicians. ResultsThe efficacy of discriminating NGBPs from non- NGBPs using deep learning was 0.944 (accuracy, 0.858; sensitivity, 0.856; specificity, 0.861). The accuracy of an unassisted diagnosis of GBP was 0.634, and that of a computer-aided diagnosis was 0.785 (p<0.001). There were no significant differences in the accuracy of a computer-aided diagnosis between experienced (0.835) and inexperienced (0.772) physicians (p = 0.251). A computer-aided diagnosis significantly assisted inexperienced physicians (0.772 vs. 0.614; p < 0.001) but not experienced physicians. ConclusionsDeep learning-based models discriminate NGBPs from non- NGBPs with excellent accuracy. As ancillary diagnostic tools, they may assist inexperienced physicians in improving their diagnostic accuracy.