MR Dictionary

Inverse variance weighted (IVW) random effects model

Combines Wald ratios (or ratio estimates) together in an inverse variance weighted (IVW) meta-analysis, adjusting for heterogeneity in two-sample MR settings. 

All genetic instrumental variables (IVs) can be invalid due to pleiotropy as long as the pleiotropy is balanced (i.e., it has a zero mean and satisfies the Instrument Strength Independent of Direct Effect – InSIDE - assumption). This means that the association of genetic IV with exposure of interest should not be associated with the path between IV and outcome that does not go via the exposure of interest. This method is asymptotically equivalent to two-stage least squares (TSLS) with uncorrelated IVs

References

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