MR G-Estimation under No Interaction with Unmeasured Selection.
Exploits the assumption that a genetic variant is a valid instrument with respect to altering the variance rather than the mean. Genetic instrument must strongly affect the variance.
- Tchetgen Tchetgen E, Sun B, Walter S. The GENIUS Approach to Robust Mendelian Randomization Inference. bioRxiv 2017:193953.