title: Nested Markov compliance class model in the presence of time-varying noncompliance.
abstract: We consider a Markov structure for partially unobserved time-varying compliance classes in the Imbens-Rubin (1997, The Annals of Statistics 25, 305-327) compliance model framework. The context is a longitudinal randomized intervention study where subjects are randomized once at baseline, outcomes and patient adherence are measured at multiple follow-ups, and patient adherence to their randomized treatment could vary over time. We propose a nested latent compliance class model where we use time-invariant subject-specific compliance principal strata to summarize longitudinal trends of subject-specific time-varying compliance patterns. The principal strata are formed using Markov models that relate current compliance behavior to compliance history. Treatment effects are estimated as intent-to-treat effects within the compliance principal strata.
authors.affiliation: Center for Multicultural Mental Health Research, Cambridge Health Alliance-Harvard Medical School, Somerville, Massachusetts 02143, USA. jlin@charesearch.org
authors.forename: Julia Y
authors.initials: JY
authors.lastname: Lin
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Ten Have
authors.forename: Michael R
authors.initials: MR
authors.lastname: Elliott