Table 1.

Overview of key assumptions, interpretations, and practical considerations of the instrumental inequalities, MR-Egger intercept test and MR-PRESSO global test

	Instrumental inequalities	MR-Egger intercept test	MR-PRESSO global test
Key assumptions in addition to the IV conditions	Coarsening of continuous exposures does not induce violations of IV conditions [31]	Homogeneity and linearity in associations between instrument, exposure, and outcome [34]	Homogeneity and linearity in associations between instrument, exposure, and outcome [35]
Example interpretations of the falsification test	(1) A global test of the IV conditions and the coarsening assumption (2) Assuming coarsening of continuous exposures did not induce violations, a test of the IV conditions	(1) A global test of the IV conditions, homogeneity, and linearity assumptions (2) Assuming homogeneity and linearity, a test of the IV conditions	(1) A global test of the IV conditions, homogeneity, and linearity assumptions (2) Assuming homogeneity and linearity, a test of the IV conditions
Considerations for statistical inference	No consensus currently exists on the optimal approach for statistical inference [40]	Often limited in power to be able detect violations of the instrumental conditions [38]	Possibly limited in power to detect violations of the instrumental conditions if the percentage of horizontal pleiotropic proposed instruments is less than 10%; less powerful to detect violations of the instrumental conditions when pleiotropy is imbalanced [35]
Applicability to one sample and/or two sample data settings	Presented approach only applicable in the one-sample setting	Has been applied in both one- and two-sample settings, but may produce biased results when applied to one sample setting [37]	Currently only applied to two-sample data settings