title: A note about the identifiability of causal effect estimates in randomized trials with non-compliance.
abstract: We show that assumptions that are sufficient for estimating an average treatment effect in randomized trials with non-compliance restrict the subgroup means for always takers, compliers, defiers and never takers to a two dimensional linear subspace of a four dimensional space. Implications and specials cases are examplified.
authors.affiliation: Departments of Biostatistics and Health Services, University of Washington, Seattle WA 98195.
authors.forename: Kwun Chuen Gary
authors.initials: KC
authors.lastname: Chan
keywords: Average treatment effect; Complier average treatment effect; Instrumental variables; Principal Stratification