Software application profile: mrrobust—a tool for performing two-sample summary Mendelian randomization analyses

MOTIVATION: In recent years, Mendelian randomization analysis using summary data from genome-wide association studies has become a popular approach for investigating causal relationships in epidemiology. The mrrobust Stata package implements several of the recently developed methods. IMPLEMENTATION: mrrobust is freely available as a Stata package. GENERAL FEATURES: The package includes inverse variance weighted estimation, as well as a range of median, modal and MR-Egger estimation methods. Using mrrobust, plots can be constructed visualizing each estimate either individually or simultaneously. The package also provides statistics such as [Formula: see text] , which are useful in assessing attenuation bias in causal estimates. AVAILABILITY: The software is freely available from GitHub [https://raw.github.com/remlapmot/mrrobust/master/].