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Physical Sciences and Mathematics Commons

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Biostatistics

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Epidemiology

Articles 1 - 3 of 3

Full-Text Articles in Physical Sciences and Mathematics

An Overview Of Statistical Approaches For Comparative Effectiveness Research For Assessing In-Hospital Complications Of Percutaneous Coronary Interventions By Access Site, Lauren Kunz, Sherri Rose, Donna Spiegelman, Sharon-Lise Normand Sep 2014

An Overview Of Statistical Approaches For Comparative Effectiveness Research For Assessing In-Hospital Complications Of Percutaneous Coronary Interventions By Access Site, Lauren Kunz, Sherri Rose, Donna Spiegelman, Sharon-Lise Normand

Sherri Rose

No abstract provided.


Causal Mediation In A Survival Setting With Time-Dependent Mediators, Wenjing Zheng, Mark J. Van Der Laan Dec 2013

Causal Mediation In A Survival Setting With Time-Dependent Mediators, Wenjing Zheng, Mark J. Van Der Laan

Wenjing Zheng

The effect of an expsore on an outcome of interest is often mediated by intermediate variables. The goal of causal mediation analysis is to evaluate the role of these intermediate variables (mediators) in the causal effect of the exposure on the outcome. In this paper, we consider causal mediation of a baseline exposure on a survival (or time-to-event) outcome, when the mediator is time-dependent. The challenge in this setting lies in that the event process takes places jointly with the mediator process; in particular, the length of the mediator history depends on the survival time. As a result, we argue …


On The Statistical Accuracy Of Biomarker Assays Of Hiv Incidence, Ron Brookmeyer Dec 2009

On The Statistical Accuracy Of Biomarker Assays Of Hiv Incidence, Ron Brookmeyer

Ron Brookmeyer

Objective: To evaluate the statistical accuracy of estimates of current HIV incidence rates from cross-sectional surveys, and to identify characteristics of assays that improve accuracy.

Methods: Performed mathematical and statistical analysis of the cross-sectional estimator of HIV incidence to evaluate bias and variance. Developed probability models to evaluate impact of long tails of the window period distribution on accuracy.

Results: The standard cross-sectional estimate of HIV incidence rate is estimating a time-lagged incidence where the lag time, called the shadow, depends on the mean and the coefficient of variation of window periods. Equations show how the shadow increases with the …