Background Antifracture efficacy with supplemental vitamin D has been questioned by recent
trials. Methods We performed a meta-analysis on the efficacy of oral supplemental vitamin …

Cardiomyopathy is a serious disorder of the heart muscle and, although rare, is a common
cause of heart failure in children, and it is also the most common cause of heart …

Background. The ongoing debate on the incidence and types of iatrogenic injuries in
American hospitals has been informed primarily by the Harvard Medical Practice Study, which …

Background— Binary angiographic and clinical restenosis rates can vary widely between
clinical studies, even for the same stent, influenced heavily by case-mix covariates that differ …

Background Risk factors for medical errors remain poorly understood. We performed a case–control
study of retained foreign bodies in surgical patients in order to identify risk factors for …

Background Vitamin D may improve muscle strength through a highly specific nuclear receptor
in muscle tissue. Objectives We investigated whether there is an association between 25-…

Context Somatoform disorders are an important determinant of medical care utilization, but
their independent effect on utilization is difficult to determine because somatizing patients …

ContextDilated cardiomyopathy (DCM) is the most common form of cardiomyopathy and
cause of cardiac transplantation in children. However, the epidemiology and clinical course of …

Objective. —To develop and validate a clinical prediction rule for postoperative delirium using
data available to clinicians preoperatively. Design. —Prospective cohort study. Setting. —…

Background Patients' perceptions of their care, especially in the hospital setting, are not well
known. Data from the Hospital Consumer Assessment of Healthcare Providers and Systems …