Mendelian randomization with Egger pleiotropy correction and weakly informative Bayesian priors.

ABSTRACT:

Background

The MR-Egger (MRE) estimator has been proposed to correct for directional pleiotropic effects of genetic instruments in an instrumental variable (IV) analysis. The power of this method is considerably lower than that of conventional estimators, limiting its applicability. Here we propose a novel Bayesian implementation of the MR-Egger estimator (BMRE) and explore the utility of applying weakly informative priors on the intercept term (the pleiotropy estimate) to increase power of the IV (slope) estimate.

Methods

This was a simulation study to compare the performance of different IV estimators. Scenarios differed in the presence of a causal effect, the presence of pleiotropy, the proportion of pleiotropic instruments and degree of 'Instrument Strength Independent o

SUBMITTER: Schmidt AF 

PROVIDER: S-EPMC6124638 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature