Y.H. has received lecture fees from Eli Lilly Japan K.K., Sanofi, Terumo Corp., Sumitomo Pharma Co., Ltd., Novo Nordisk Pharma Ltd., Abbott Japan LLC., Medtronic Japan Co., Ltd., Dexcom Inc., Mitsubishi Tanabe Pharma Co., Daiichi Sankyo Co., Teijin Pharma Ltd., Sanwa Kagaku Kenkyusho Co., Novartis Pharma K.K., Kyowa Kirin Co., Ltd., Roche Diagnostics K.K., Kowa Co., Ltd., Otsuka Pharmaceutical Co., Ltd., Nippon Boehringer Ingelheim Co., Ltd., LifeScan Japan K.K., Nipro Corp., Mochida Pharmaceutical Co., Ltd.; research expenses (including for contracted research, joint research, and clinical trials) and grants from Sumitomo Pharma Co., Ltd., Kyowa Kirin Co., Ltd., Medtronic Japan Co., Ltd., and Nippon Boehringer Ingelheim Co., Ltd.; and scholarship donations from Abbott Japan LLC. A.Y. has received lecture fees from Sanofi K.K. T.T. has received lecture fees from Taisho Pharmaceutical Co., Ltd. A.T. has received lecture fees from Sanofi K.K. K.Yokota has received lecture fees from DAIICHI SANKYO, INC., AstraZeneca K.K., Bayer Yakuhin, Ltd., Astellas Pharma Inc., TERUMO CORPORATION, Nippon Boehringer Ingelheim Co., Ltd., Kowa Co., Ltd., Sumitomo Pharma Co., Ltd., Taisho Pharmaceutical Co., Ltd., Otsuka Pharmaceutical Co., Ltd., Eli Lilly Japan K.K., Novartis Pharmaceuticals, Novo Nordisk Pharma Ltd., Mitsubishi Tanabe Pharma Corporation, KISSEI PHARMACEUTICAL CO., LTD., Kyowa Kirin Co Ltd, Mochida Pharmaceutical Co., Ltd. K.S. received provision of study materials, and has received lecture fees from MSD K.K., Astellas Pharma Inc., AstraZeneca K.K., Otsuka Pharmaceutical Co., Ltd., Kowa Co., Ltd., Sanofi K.K., Sumitomo Pharma Co., Ltd., Taisho Pharmaceutical Co., Ltd., Mitsubishi Tanabe Pharma Corporation, Nippon Boehringer Ingelheim Co., Ltd., Novartis Pharma K.K., Novo Nordisk Pharma Ltd., Bayer Yakuhin, Ltd., Eli Lilly Japan K.K. W.O. has received lecture fees from Eli Lilly Japan K.K., Sanofi K.K., Terumo Corp., Sumitomo Pharma Co., Ltd., Novo Nordisk Pharma Ltd., Abbott Japan LLC, Teijin Pharma Ltd., Johnson & Johnson K.K., Nippon Boehringer Ingelheim Co., Ltd., Kyowa Kirin Co. Ltd., Kissei Pharmaceutical Co., Ltd., Kowa Co. Ltd., Takeda Pharmaceutical Co., Ltd., Astellas Pharma Inc., MSD K.K., Mitsubishi Tanabe Pharma Co., Chugai Pharmaceutical Co., Ltd., Eisai Co., Ltd., Viatris Pharmaceuticals, LLC, Taisho Pharmaceutical Co. Ltd., Amgen K.K., Noster Inc., Pfizer Japan Inc.; research grants from Sumitomo Pharma Co., Ltd., Eli Lilly Japan K.K., Noster Co., Ltd., Nippon Boehringer Ingelheim Co., Ltd., Novo Nordisk Pharma Ltd., Mochida Pharmaceutical Co., Ltd., Kowa Co. Ltd., and Taisho Pharmaceutical Co. Ltd. All other authors declare that they have no conflicts of interest.

The study was conducted from January 2018 to January 2023. It was approved by Kobe University Clinical Research Review Board (accreditation no. CRB5180009) on 18 January 2018, registered with Japan Registry of Clinical Trials (jRCTs052180079) on 27 February 2019, and performed in accordance with the principles of the Declaration of Helsinki and with the CONSORT guidelines.