9 citations · 17 across the 9 of their papers we have counts for
4 papers · 1 filter
Improving Precision through Adjustment for Prognostic Variables in Group Sequential Trial Designs: Impact of Baseline Variables, Short-Term Outcomes, and Treatment Effect Heterogeneity
Tianchen Qian, Michael Rosenblum, Huitong Qiu
In randomized trials, appropriately adjusting for baseline variables and short-term outcomes can lead to increased precision and reduced sample size. We examine the impact of such…
Estimating Time-Varying Causal Excursion Effect in Mobile Health with Binary Outcomes
Tianchen Qian, Hyesun Yoo, Predrag Klasnja +2
Advances in wearables and digital technology now make it possible to deliver behavioral mobile health interventions to individuals in their everyday life. The micro-randomized tria…
Deductive semiparametric estimation in Double-Sampling Designs with application to PEPFAR
Tianchen Qian, Constantine Frangakis, Constantin Yiannoutsos
Non-ignorable dropout is common in studies with long follow-up time, and it can bias study results unless handled carefully. A double-sampling design allocates additional resources…
Linear mixed models with endogenous covariates: modeling sequential treatment effects with application to a mobile health study
Tianchen Qian, Predrag Klasnja, Susan A. Murphy
Mobile health is a rapidly developing field in which behavioral treatments are delivered to individuals via wearables or smartphones to facilitate health-related behavior change. M…