Study design and participants
kidney stone
MAY, KIDNEY STONE
This study was a parallel-group randomized controlled clinical trial undertaken in the kidney stone prevention clinic of Shahid Labbafinejad medical center, from April 2018 to May 2020. The patients were recurrent calcium stone formers who had serum 25-hydroxyvitamin D (25(OH)D) level of 10–20 ng/mL, aged 18–70 years, had body mass index (BMI) of less than 30 kg/mThe study was approved by the ethics committee of the Urology and Nephrology Research Center, Shahid Beheshti University of Medical Sciences (IR. SBMU.UNRC.1395.26), and Tehran University of Medical Sciences (IR.TUMS.VCR.REC.1397.193). The trial was registered in the Iranian Registry of Clinical Trials (IRCT) (IRCT20160206026406N4). All the study protocols were performed in accordance with the 1964 Declaration of Helsinki, and all participants gave written informed consent before the study.