Impact of 3-second rule for high confidence assignment on the performance of endoscopists for the real-time optical diagnosis of colorectal polyps

Background Confusion between high and low confidence decisions in optical diagnosis hinders the implementation of real-time optical diagnosis in clinical practice. We evaluated the effect of a 3-second rule (decision time limited to 3 seconds for a high confidence assignment) in expert and nonexpert endoscopists.Methods This single-center prospective study included eight board-certified gastroenterologists. A 2-month baseline phase used standard real-time optical diagnosis for colorectal polyps <10 mm and was followed by a 6-month intervention phase using optical diagnosis with the 3 -second rule. Performance, including high confidence accuracy, and Preservation and Incorporation of Valuable Endoscopic Innovations (PIVI) and Simple Optical Diagnosis Accuracy (SODA) thresholds, was measured.Results Real-time optical diagnosis was performed on 1793 patients with 3694 polyps. There was significant improve-ment in high confidence accuracy between baseline and in-tervention phases in the nonexpert group (79.2 % vs. 86.3%; P = 0.01) but not in the expert group (85.3% vs. 87.5%; P=0.53). Using the 3-second rule improved the overall per-formance of PIVI and SODA in both groups.Conclusions The 3-second rule was effective in improving real-time optical diagnosis performance, especially in non -experts.