IV假设

Genetic instruments G1

Type 2 diabetes

(2b)

Genetic instruments G2

(3b)

(2a)

Hepatocellular carcinoma

(1a)

(1b)

Confounders

(3a)

(1a) G1 are robustly associated with type 2 diabetes(1b) G2 are robustly associated with hepatocellular carcinoma(2a) G1 are not associated with the confounding variables(2b) G2 are not associated with the confounding variables(3a) G1 are only associated with hepatocellular carcinoma via type 2 diabetes(3b) G2 are only associated with type 2 diabetes via hepatocellular carcinoma