Benchmarking definitions of false-positive alerts during computer-aided polyp detection in colonoscopy

Background The occurrence of false-positive alerts is an important outcome measure in computer-aided colon polyp detection (CADe) studies. However, there is no consensus definition of a false positive in clinical trials evaluating CADe in colonoscopy. We aimed to study the diagnostic performance of CADe based on different threshold definitions for false-positive alerts. Methods A previously validated CADe system was applied to screening/surveillance colonoscopy videos. Different thresholds for false-positive alerts were defined based on the time an alert box was continuously traced by the system. Primary outcomes were false-positive results and specificity using different threshold definitions of false positive. Results 62 colonoscopies were analyzed. CADe specificity and accuracy were 93.2% and 97.8%, respectively, for a threshold definition of >= 0.5 seconds, 98.6% and 99.5% for a threshold definition of >= 1 second, and 99.8% and 99.9% for a threshold definition of >= 2 seconds. Conclusion Our analysis demonstrated how different threshold definitions of false positive can impact the reported diagnostic performance of CADe for colon polyp detection.