Fig. 1
From: The association between basal metabolic rate and osteoarthritis: a Mendelian randomization study
The schematic representation of this study and the three assumptions of Mendelian randomization analysis: (1) The used genetic IVs are independent of the currently known confounding factors. (2) The selected IVs are closely related to BMR. (3) The selected SNPs have no direct influence on the outcome of osteoarthritis, but only influence the outcome through basal metabolic rate.