mr_steiger: MR Steiger test of directionality

In MRCIEU/TwoSampleMR: Two Sample MR Functions and Interface to MR Base Database

MR Steiger test of directionality

Description

A statistical test for whether the assumption that exposure causes outcome is valid

Usage

mr_steiger(p_exp, p_out, n_exp, n_out, r_exp, r_out, r_xxo = 1, r_yyo = 1, ...)

Arguments

p_exp	Vector of p-values of SNP-exposure
p_out	Vector of p-values of SNP-outcome
n_exp	Sample sizes for p_exp
n_out	Sample sizes for p_out
r_exp	Vector of absolute correlations for SNP-exposure
r_out	Vector of absolute correlations for SNP-outcome
r_xxo	Measurememt precision of exposure
r_yyo	Measurement precision of outcome
...	Further arguments to be passed to lattice::wireframe()

Value

List with the following elements:

r2_exp

Estimated variance explained in x

r2_out

Estimated variance explained in y

r2_exp_adj

Predicted variance explained in x accounting for estimated measurement error

r2_out_adj

Predicted variance explained in y accounting for estimated measurement error

correct_causal_direction

TRUE/FALSE

steiger_test

p-value for inference of direction

correct_causal_direction_adj

TRUE/FALSE, direction of causality for given measurement error parameters

steiger_test_adj

p-value for inference of direction of causality for given measurement error parameters

vz

Total volume of the error parameter space

vz0

Volume of the parameter space that gives the incorrect answer

vz1

Volume of the paramtere space that gives the correct answer

sensitivity_ratio

Ratio of vz1/vz0. Higher means inferred direction is less susceptible to measurement error

sensitivity_plot

Plot of parameter space of causal directions and measurement error

MRCIEU/TwoSampleMR documentation built on April 22, 2024, 8:42 p.m.