The MBD-5D is a 3-year prospective observational study with a case-cohort and a cohort design. Eligible patients comprise all patients who are receiving hemodialysis at the participating facilities, and who also have secondary hyperparathyroidism(2HPT). The study has 3 goals: to record the characteristics of those patients and variation in the patterns of their treatment; to analyze factors associated with variation in those medical practice patterns; and to identify the practice patterns and other factors that affect hospitalization, mortality, and other patient-level outcomes. In the case-cohort study, the outcomes are relatively infrequent events (all-cause and cardiovascular mortality). The cohort study includes a randomly selected sample of 40% of all study participants; and the outcomes are hospitalization, parathyroid interventions, bone fracture, MBD management status, etc. Explanatory variables comprise medications and other factors likely to be associated with outcomes of dialysis and of 2HPT, and facility-level practice patterns.
