Author contributions
All named authors meet the International Committee of Medical Journal Editors (ICMJE) criteria for authorship of this manuscript. Naoto Katakami and Tomoya Mita contributed to the conception and design of the study, development and amendment of the study protocol, subject enrollment and study implementation, data collection, discussion, writing, reviewing, and editing of this manuscript. Hirotaka Watada and Iichiro Shimomura supervised the conception, design, discussion, and reviewing of this manuscript. Other authors contributed to subject enrollment and study implementation, data collection, discussion, and review of this manuscript. All authors approved the final version of the manuscript. Naoto Katakami is the guarantor of this work and, as such, had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.