Acknowledgements
All named authors meet the International Committee of Medical Journal Editors criteria for authorship for this article, take responsibility for the integrity of the work, and have given their approval for this version to be published. Medical writing, editorial, and other assistance: The authors thank Ms Phonsuk Yamlexnoi, Ms Chutikan Kiatphansodsai, Ms Apichaya Jutaphonrakul, and Dr Surachet Sirisuthivoranunt for their assistance in recruiting subjects and managing the database. The authors express their gratitude to Mr Suthipol Udompunthurak for his assistance with the statistical analyses. The authors are also indebted to Mr David Park for English-language editing. We thank the patients who participated in the study.