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We introduce random survival forests, a random forests method for the analysis of right-censored survival data. New survival splitting rules for growing survival trees are introduced, as is a new missing data algorithm for im-puting missing data. A conservation-of-events principle for survival forests is introduced and used to define ensemble mortality, a(More)
The minimal depth of a maximal subtree is a dimensionless order statistic measuring the predictiveness of a variable in a survival tree. We derive the distribution of the minimal depth and use it for high-dimensional variable selection using random survival forests. In big p and small n problems (where p is the dimension and n is the sample size), the(More)
An ambulatory medical record system was implemented as a pilot project to determine the clinical and operational impacts of using interactive, computer-based systems in the outpatient setting. Of the 58 physicians who attempted to use the AMR system, 28 continue as active users. Physicians who discontinued use of the system reported a variety of reasons for(More)
OBJECTIVES The purpose of this study was to externally validate the prognostic value of age- and gender-based nomograms and categorical definitions of impaired exercise capacity (EC). BACKGROUND Exercise capacity predicts death, but its use in routine clinical practice is hampered by its close correlation with age and gender. METHODS For a median of 5(More)
The increasing availability of personal genomic tests has led to discussions about the validity and utility of such tests and the balance of benefits and harms. A multidisciplinary workshop was convened by the National Institutes of Health and the Centers for Disease Control and Prevention to review the scientific foundation for using personal genomics in(More)
PERSPECTIVE 1579 level playing field for all stake-holders. What is sometimes labeled as " free riding " may ultimately pay dividends for innovative companies and for public health. It is ironic that the organizations that most resist wider access to data are the ones that stand to benefit so much from greater transparency. The views expressed in this(More)
FL and a paper entitled " Use of the "Logical Analysis of Data" Method for Assessing Long-Term Mortality Risk After Exercise Electrocardiography " was submitted for publication to a medical journal. Abstract The objective of this study was to distinguish within a population of patients with known or suspected coronary artery disease groups at high and at(More)
Recent studies have confirmed heart rate fall after treadmill exercise testing, or heart rate recovery, as a powerful predictor of mortality from heart disease. Heart rate recovery depends on central reactivation of vagal tone and decreased vagal activity is a risk factor for death. If heart rate recovery is defined as the fall in heart rate after 1 minute(More)