A novel method for controlling unobserved confounding using double confounders.

ABSTRACT:

Background

Controlling unobserved confounding still remains a great challenge in observational studies, and a series of strict assumptions of the existing methods usually may be violated in practice. Therefore, it is urgent to put forward a novel method.

Methods

We are interested in the causal effect of an exposure on the outcome, which is always confounded by unobserved confounding. We show that, the causal effect of an exposure on a continuous or categorical outcome is nonparametrically identified through only two independent or correlated available confounders satisfying a non-linear condition on the exposure. Asymptotic theory and variance estimators are developed for each case. We also discuss an extension for more than two binary confounders.

Results

The simulat

SUBMITTER: Liu L 

PROVIDER: S-EPMC7374896 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature