Special thanks to Janice L. Contini, Head Reference Librarian at the UCLA, and Louise M. Darling Biomedical Library, who helped us develop our search strategy. Special thanks also to Janet D. Elashoff, Ph.D., Director of Biostatistics Core Research Institute at Cedars‐Sinai Medical Center, who helped us develop our statistical approaches for carrying out our analyses. Special thanks to Dr. Dong Ki Lee who provided a Korean to English translation for one of the articles. Great thanks to Dr. Ronald Koretz, Chief of Gastroenterology at UCLA ‐ Olive View Medical Center, who contributed significant mentoring to the development of the protocol and to the final systematic review.