MR Dictionary

MR-Egger regression and extensions

Combines Wald ratio (or Ratio estimates) together into a meta-regression (with an intercept and slope parameter) to estimate the causal effect adjusted for any directional pleiotropy

All SNPs can be invalid due to pleiotropy as long as the pleiotropy satisfies the InSIDE assumption. Can be implemented in a Bayesian framework. Standard implementation requires gene-exposure associations to be orientated in positive direction. Radial MR formulation avoids this step. The intercept of a MR-Egger regression provides an indication of pleiotropy when it is not null. Similar to IVW methods, the NOME assumption still holds and, if violated, there may be weak instrument bias. This can be tested with the I2 statistic with the MR-Egger method. 


Other terms in 'Pleiotropy-robust two-sample MR methods':