Study population
MAY, HYPERVITAMINOSIS D, UROLITHIASIS, HYPERCALCEMIA
Patients, age 18 or above, at the Leukemia/Bone Marrow Transplant Program of British Columbia undergoing aHSCT during May 2018 to June 2019 were screened and invited to participate in the study. Individuals with a history of urolithiasis, hypercalcemia, hypervitaminosis D (25(OH)D >375 nmol/L), or sensitivity to vit D supplements were excluded. There was no vit D level requirement or restriction to be enrolled to this study. The study protocol was reviewed and approved by the University of British Columbia Research Ethics Board. All enrolled patients provided written informed consent. This study was registered at ClinicalTrials.gov (NCT03534674).