Bayesian Inference for Multivariate Meta-regression with a Partially Observed Within-Study Sample Covariance Matrix.

TitleBayesian Inference for Multivariate Meta-regression with a Partially Observed Within-Study Sample Covariance Matrix.
Publication TypeJournal Article
Year of Publication2015
AuthorsYao, Hui, Sungduk Kim, Ming-Hui Chen, Joseph G. Ibrahim, Arvind K. Shah, and Jianxin Lin
JournalJ Am Stat Assoc
Date Published2015 Jun

Multivariate meta-regression models are commonly used in settings where the response variable is naturally multi-dimensional. Such settings are common in cardiovascular and diabetes studies where the goal is to study cholesterol levels once a certain medication is given. In this setting, the natural multivariate endpoint is Low Density Lipoprotein Cholesterol (LDL-C), High Density Lipoprotein Cholesterol (HDL-C), and Triglycerides (TG) (LDL-C, HDL-C, TG). In this paper, we examine study level (aggregate) multivariate meta-data from 26 Merck sponsored double-blind, randomized, active or placebo-controlled clinical trials on adult patients with primary hypercholesterolemia. Our goal is to develop a methodology for carrying out Bayesian inference for multivariate meta-regression models with study level data when the within-study sample covariance matrix for the multivariate response data is partially observed. Specifically, the proposed methodology is based on postulating a multivariate random effects regression model with an unknown within-study covariance matrix Σ in which we treat the within-study sample correlations as missing data, the standard deviations of the within-study sample covariance matrix are assumed observed, and given Σ, follows a Wishart distribution. Thus, we treat the off-diagonal elements of as missing data, and these missing elements are sampled from the appropriate full conditional distribution in a Markov chain Monte Carlo (MCMC) sampling scheme via a novel transformation based on partial correlations. We further propose several structures (models) for Σ, which allow for borrowing strength across different treatment arms and trials. The proposed methodology is assessed using simulated as well as real data, and the results are shown to be quite promising.

Alternate JournalJ Am Stat Assoc
Original PublicationBayesian inference for multivariate meta-regression with a partially observed within-study sample covariance matrix.
PubMed ID26257452
PubMed Central IDPMC4524568
Grant ListP01 CA142538 / CA / NCI NIH HHS / United States
R01 CA074015 / CA / NCI NIH HHS / United States
R01 GM070335 / GM / NIGMS NIH HHS / United States