Author Contributions: Dr Chan had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: A. O. O. Chan, Jim, Morris, Lai, S. K. Lam.
Acquisition of data: A. O. O. Chan, Jim, Siu, Tong, Ng, S. Y. Wong, C. K. Chan, Cheung, P. Chan, G. Wong, Yuen, Lau, Lee, B. C. Y. Wong.
Analysis and interpretation of data: A. O. O. Chan, K. F. Lam, Morris, Hui.
Drafting of the manuscript:A. O. O. Chan, Tong, C. K. Chan, Lai, P. Chan, Lau, Szeto, S. K. Lam.
Critical revision of the manuscript for important intellectual content: A. O. O. Chan, Jim, K. F. Lam, Morris, Siu, Ng, S. Y. Wong, Hui, Cheung, Yuen, Lee.
Statistical analysis: A. O. O. Chan, K. F. Lam, Morris.
Obtained funding: A. O. O. Chan, S. K. Lam.
Administrative, technical, or material support: A. O. O. Chan.
Study supervision: A. O. O. Chan.
Financial Disclosures: None reported.
Funding/Support: The study was partially sponsored by the Gastrointestinal Cancer Research Fund, University of Hong Kong.
Role of the Sponsor: The Gastrointestinal Cancer Research Fund had no role in the design and conduct of the study, in the collection, analysis, and interpretation of the data, or in the preparation, review, or approval of the manuscript.