When should factorial designs be used for late-phase randomised controlled trials?

ABSTRACT:

Background

A 2×2 factorial design evaluates two interventions (A versus control and B versus control) by randomising to control, A-only, B-only or both A and B together. Extended factorial designs are also possible (e.g. 3×3 or 2×2×2). Factorial designs often require fewer resources and participants than alternative randomised controlled trials, but they are not widely used. We identified several issues that investigators considering this design need to address, before they use it in a late-phase setting.

Methods

We surveyed journal articles published in 2000-2022 relating to designing factorial randomised controlled trials. We identified issues to consider based on these and our personal experiences.

Results

We identified clinical, practical, statistical and external

SUBMITTER: White IR 

PROVIDER: S-EPMC7615816 | biostudies-literature | 2024 Apr

REPOSITORIES: biostudies-literature