Research Paper Volume 16, Issue 5 pp 4723—4735
A Mendelian randomization analysis identifies causal association between sarcopenia and gastroesophageal reflux disease
Figure 1. The overall flow chart of the MR study. Assumption 1 is that the genetic variants used as instrumental variables should be robustly associated with the exposure; assumption 2 is that the used genetic variants should not be associated with any confounders; and the assumption 3 is that the used instrumental variables should affect the risk of the outcome solely through the exposure, not via other pathways. GERD, gastroesophageal reflux disease; IV, instrumental variable; SNP, single nucleotide polymorphism; MR, Mendelian randomization; MR-PRESSO, Mendelian randomization pleiotropy residual sum and outlier; IVW, inverse variance weighted; MVMR, multivariable Mendelian randomization.