Measurement bias: a structural perspective
Abstract
The causal structure for measurement bias (MB) remains controversial. Aided by the Directed Acyclic Graph (DAG), this paper proposes a new structure for measuring one singleton variable whose MB arises in the selection of an imperfect I/O device-like measurement system. For effect estimation, however, an extra source of MB arises from any redundant association between a measured exposure and a measured outcome. The misclassification will be bidirectionally differential for a common outcome, unidirectionally differential for a causal relation, and non-differential for a common cause between the measured exposure and the measured outcome or a null effect. The measured exposure can actually affect the measured outcome, or vice versa. Reverse causality is a concept defined at the level of measurement. Our new DAGs have clarified the structures and mechanisms of MB.
Cite
@article{arxiv.2012.10980,
title = {Measurement bias: a structural perspective},
author = {Yijie Li and Wei Fan and Miao Zhang and Lili Liu and Jiangbo Bao and Yingjie Zheng},
journal= {arXiv preprint arXiv:2012.10980},
year = {2020}
}