Format

Send to

Choose Destination
See comment in PubMed Commons below
Am J Epidemiol. 2012 Mar 1;175(5):381-90. doi: 10.1093/aje/kwr346. Epub 2012 Feb 1.

Marginal structural models for case-cohort study designs to estimate the association of antiretroviral therapy initiation with incident AIDS or death.

Author information

1
Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, 27599-7435, USA. cole@unc.edu

Erratum in

  • Am J Epidemiol. 2012 Apr 1;175(7):732.

Abstract

To estimate the association of antiretroviral therapy initiation with incident acquired immunodeficiency syndrome (AIDS) or death while accounting for time-varying confounding in a cost-efficient manner, the authors combined a case-cohort study design with inverse probability-weighted estimation of a marginal structural Cox proportional hazards model. A total of 950 adults who were positive for human immunodeficiency virus type 1 were followed in 2 US cohort studies between 1995 and 2007. In the full cohort, 211 AIDS cases or deaths occurred during 4,456 person-years. In an illustrative 20% random subcohort of 190 participants, 41 AIDS cases or deaths occurred during 861 person-years. Accounting for measured confounders and determinants of dropout by inverse probability weighting, the full cohort hazard ratio was 0.41 (95% confidence interval: 0.26, 0.65) and the case-cohort hazard ratio was 0.47 (95% confidence interval: 0.26, 0.83). Standard multivariable-adjusted hazard ratios were closer to the null, regardless of study design. The precision lost with the case-cohort design was modest given the cost savings. Results from Monte Carlo simulations demonstrated that the proposed approach yields approximately unbiased estimates of the hazard ratio with appropriate confidence interval coverage. Marginal structural model analysis of case-cohort study designs provides a cost-efficient design coupled with an accurate analytic method for research settings in which there is time-varying confounding.

PMID:
22302074
PMCID:
PMC3282878
DOI:
10.1093/aje/kwr346
[Indexed for MEDLINE]
Free PMC Article

Publication type, MeSH terms, Substance, Grant support

Publication type

MeSH terms

Substance

Grant support

PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Silverchair Information Systems Icon for PubMed Central
    Loading ...
    Support Center