Two-stage least squares (TSLS)

The canonical method to estimate the causal effect of a continuous exposure on a continuous outcome using an IV. 

Genetic variants must satisfy the IV assumptions. Gene-outcome model must be correctly specified. 

References

• Brunner K. The American Economic Review 1955;45:680-682.

Other terms in 'One-sample MR methods':

• Generalized Method of Moments (GMM) estimator
• MR with a time-to-event outcome
• Non-parametric methods with bounds of causal effect
• Polygenic risk score approach
• Semi-parametric structural mean model (SMMs) for binary outcomes
• TSLS with binary outcome