Subtle issues in model specification and estimation of marginal structural models
Article first published online: 16 JAN 2012
Copyright © 2012 John Wiley & Sons, Ltd.
Pharmacoepidemiology and Drug Safety
Volume 21, Issue 3, pages 241–245, March 2012
How to Cite
Yang, W. and Joffe, M. M. (2012), Subtle issues in model specification and estimation of marginal structural models. Pharmacoepidem. Drug Safe., 21: 241–245. doi: 10.1002/pds.2306
- Issue published online: 8 MAR 2012
- Article first published online: 16 JAN 2012
- Manuscript Revised: 19 OCT 2011
- Manuscript Accepted: 19 OCT 2011
- Manuscript Received: 17 MAY 2011
We review the concept of time-dependent confounding by using the example in paper “Comparative effectiveness of individual angiotensin receptor blockers on risk of mortality in patients with chronic heart failure” by Desai et al. and illustrate how to adjust for it by using inverse probability of treatment weighting through a simulated example. We discuss a few subtle issues that arise in specification of the model for treatment required to fit marginal structural models (MSMs) and in specification of the structural model for the outcome. We discuss the differences between the effects estimated in MSMs and intention-to-treat effects estimated in randomized trials, followed by an outline of some limitations of MSMs. Copyright © 2012 John Wiley & Sons, Ltd.