Demystifying optimal dynamic treatment regimes.
A dynamic regime is a function that takes treatment and covariate history and baseline covariates as inputs and returns a decision to be made. Murphy (2003, Journal of the Royal Statistical Society, Series B 65, 331-366) and Robins (2004, Proceedings of the Second Seattle Symposium on Biostatistics, 189-326) have proposed models and developed semiparametric methods for making inference about the optimal regime in a multi-interval trial that provide clear advantages over traditional parametric approaches. We show that Murphy's model is a special case of Robins's and that the methods are closely related but not equivalent. Interesting features of the methods are highlighted using the Multicenter AIDS Cohort Study and through simulation.
Moodie
Erica E M
EE
Department of Biostatistics, University of Washington, Seattle, Washington 98195, USA. erica.moodie@mcgill.ca
Richardson
Thomas S
TS
Stephens
David A
DA
D000163:Acquired Immunodeficiency Syndrome / Q000188:drug therapy / Q000276:immunology; D000465:Algorithms; D019380:Anti-HIV Agents / Q000008:administration & dosage / Q000627:therapeutic use; D001699:Biometry; D018791:CD4 Lymphocyte Count; D002986:Clinical Trials as Topic / Q000706:statistics & numerical data*; D015331:Cohort Studies; D006801:Humans; D015233:Models, Statistical; D015337:Multicenter Studies as Topic / Q000706:statistics & numerical data; D011897:Random Allocation; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D013997:Time Factors; D015215:Zidovudine / Q000008:administration & dosage / Q000627:therapeutic use
D019380:Anti-HIV Agents; D015215:Zidovudine