Published online Apr 14, 2019. doi: 10.3748/wjg.v25.i14.1666
Peer-review started: February 12, 2019
First decision: February 26, 2019
Revised: March 4, 2019
Accepted: March 16, 2019
Article in press: March 16, 2019
Published online: April 14, 2019
Core tip: Artificial intelligence (AI) using deep-learning (DL) has emerged as a breakthrough computer technology. The convolutional neural network exhibited outstanding performance in image analysis. AI has been applied in the field of gastroenterology in terms of diagnosis, prognosis, and image analysis. However, potential inherent pitfalls of selection bias, overfitting, and spectrum bias (class imbalance) have the possibility of overestimating the accuracy and generalizing the result. Therefore, external validation using unused datasets for model development, collected in a way that minimizes the spectrum bias, is mandatory. DL has its own lack of interpretability, and further investigations should be performed on this issue.