Figure 3.Three assumptions about glucocorticoid medication use, senile cataract and iridocyclitis in this Mendelian randomization study. (i) The instrument variables (IVs) are strongly associated with iridocyclitis and glucocorticoid medication use; (ii) the genetic IVs are independent of confounders; (iii) the genetic IVs affect senile cataract only through their effect on iridocyclitis and glucocorticoid medication use, and not through an alternative causal pathway.
