This article summarizes recommendations on the design and conduct of clinical trials of a National Research Council study on missing data in clinical trials. Key findings of the study are that (a) substantial missing data is a serious problem that undermines the scientific credibility of causal conclusions from clinical trials; (b) the assumption that analysis… Continue reading The design and conduct of clinical trials to limit missing data
Keyword: *Data Interpretation
A shrinkage approach for estimating a treatment effect using intermediate biomarker data in clinical trials
In clinical trials, a biomarker (S ) that is measured after randomization and is strongly associated with the true endpoint (T) can often provide information about T and hence the effect of a treatment (Z ) on T. A useful biomarker can be measured earlier than T and cost less than T. In this article,… Continue reading A shrinkage approach for estimating a treatment effect using intermediate biomarker data in clinical trials
A functional multiple imputation approach to incomplete longitudinal data
In designed longitudinal studies, information from the same set of subjects are collected repeatedly over time. The longitudinal measurements are often subject to missing data which impose an analytic challenge. We propose a functional multiple imputation approach modeling longitudinal response profiles as smooth curves of time under a functional mixed effects model. We develop a… Continue reading A functional multiple imputation approach to incomplete longitudinal data
On using summary statistics from an external calibration sample to correct for covariate measurement error
BACKGROUND: Covariate measurement error is common in epidemiologic studies. Current methods for correcting measurement error with information from external calibration samples are insufficient to provide valid adjusted inferences. We consider the problem of estimating the regression of an outcome Y on covariates X and Z, where Y and Z are observed, X is unobserved, but… Continue reading On using summary statistics from an external calibration sample to correct for covariate measurement error