Online Program Home
My Program

Abstract Details

Activity Number: 505 - Flexible Methods for Causality Research
Type: Topic Contributed
Date/Time: Wednesday, August 1, 2018 : 10:30 AM to 12:20 PM
Sponsor: Section on Statistics in Epidemiology
Abstract #328723 Presentation
Title: Generalizability of Causal Inference in Observational Studies Under Retrospective Convenience Sampling
Author(s): Zonghui Hu* and Jing Qin
Companies: National Institute of Health and National Institute of Allergy and Infectious Diseases, NIH
Keywords: Causal inference; Generalizability; Observational study; Propensity score; Retrospective convenience sampling

For ethical and cost-effective considerations, some observational studies adopt a "retrospective convenience sampling (RCS)". With the sample size in each arm pre-specified, RCS randomly select subjects from the treatment-inclined subpopulation into the treatment arm, and those from the control-inclined into the control arm. Samples in each arm are representative of the respective subpopulation, but the proportion of the two subpopulations is usually not preserved in the sample data. We show in this work that, under RCS, existing causal effect estimators actually estimate the treatment effect over the sample population instead of the underlying study population. We investigate how to correct existing methods for consistent estimation of the treatment effect over the underlying population. When the tendency to receive treatment is low in a study population, the corrected treatment effect estimators under RCS is more efficient than their parallels under random sampling. These properties are investigated theoretically and through numerical studies.

Authors who are presenting talks have a * after their name.

Back to the full JSM 2018 program