Clarifying identification and estimation of treatment effects in the Sequential Parallel Comparison Design
Fuente:
arXiv
Saved in:
| Main Authors: | , , , , , , , , , , |
|---|---|
| Format: | Preprint |
| Published: |
2025
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866911371130568704 |
|---|---|
| author | Stockton, Benjamin Santacatterina, Michele Mandal, Soutrik Cleland, Charles M. Hade, Erinn M. Illenberger, Nicholas Meropol, Sharon Troxel, Andrea B. Petkova, Eva Yu, Chang Tarpey, Thaddeus |
| author_facet | Stockton, Benjamin Santacatterina, Michele Mandal, Soutrik Cleland, Charles M. Hade, Erinn M. Illenberger, Nicholas Meropol, Sharon Troxel, Andrea B. Petkova, Eva Yu, Chang Tarpey, Thaddeus |
| contents | Sequential parallel comparison design (SPCD) clinical trials aim to adjust active treatment effect estimates for placebo response to minimize the impact of placebo responders on the estimates. This is potentially accomplished using a two stage design by measuring treatment effects among all participants during the first stage, then classifying some placebo arm participants as placebo non-responders who will be re-randomized in the second stage. In this paper, we use causal inference tools to clarify under what assumptions treatment effects can be identified in SPCD trials and what effects the conventional estimators target at each stage of the SPCD trial. We further illustrate the highly influential impact of placebo response misclassification on the second stage estimate. We conclude that the conventional SPCD estimators do not target meaningful treatment effects. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2511_19677 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Clarifying identification and estimation of treatment effects in the Sequential Parallel Comparison Design Stockton, Benjamin Santacatterina, Michele Mandal, Soutrik Cleland, Charles M. Hade, Erinn M. Illenberger, Nicholas Meropol, Sharon Troxel, Andrea B. Petkova, Eva Yu, Chang Tarpey, Thaddeus Methodology Applications 62P10 Sequential parallel comparison design (SPCD) clinical trials aim to adjust active treatment effect estimates for placebo response to minimize the impact of placebo responders on the estimates. This is potentially accomplished using a two stage design by measuring treatment effects among all participants during the first stage, then classifying some placebo arm participants as placebo non-responders who will be re-randomized in the second stage. In this paper, we use causal inference tools to clarify under what assumptions treatment effects can be identified in SPCD trials and what effects the conventional estimators target at each stage of the SPCD trial. We further illustrate the highly influential impact of placebo response misclassification on the second stage estimate. We conclude that the conventional SPCD estimators do not target meaningful treatment effects. |
| title | Clarifying identification and estimation of treatment effects in the Sequential Parallel Comparison Design |
| topic | Methodology Applications 62P10 |
| url | https://arxiv.org/abs/2511.19677 |