episensr (version 1.3.0)

mbias: Sensitivity analysis to correct for selection bias caused by M bias.

Description

Simple sensitivity analysis to correct for selection bias caused by M bias using estimates of the odds ratios relating the variables.

Usage

mbias(or, var = c("y", "x", "a", "b", "m"))

Value

A list with elements:

model

Bias analysis performed.

mbias.parms

Three maximum bias parameters: in collider-exposure relationship created by conditioning on the collider, in collider-outcome relationship created by conditioning on the collider, and in exposure-outcome relationship created by conditioning on the collider.

adj.measures

Selection bias corrected odds ratio.

bias.parms

Input bias parameters.

labels

Variables' labels.

Arguments

or

Vector defining the input bias parameters, in the following order:

1. Odds ratio between A and the exposure E,

2. Odds ratio between A and the collider M,

3. Odds ratio between B and the collider M,

4. Odds ratio between B and the outcome D,

5. Odds ratio observed between the exposure E and the outcome D.

var

Vector defining variable names, in the following order:

1. Outcome,

2. Exposure,

3. A,

4. B,

5. Collider.

References

Greenland S. Quantifying biases in causal models: classical confounding vs. collider-stratification bias. Epidemiology 2003;14:300-6.

Examples

mbias(or = c(2, 5.4, 2.5, 1.5, 1),
var = c("HIV", "Circumcision", "Muslim", "Low CD4", "Participation"))