Power and sample size calculation for non-inferiority trials with treatment switching in intention-to-treat analysis comparing RMSTs.

ABSTRACT:

Background

Difference in Restricted Mean Survival Time (DRMST) has attracted attention and is increasingly used in non-inferiority (NI) trials because of its superior power in detecting treatment effects compared to hazard ratio. However, when treatment switching (also known as crossover) occurs, the widely used intention-to-treat (ITT) analysis can underpower or overpower NI trials.

Methods

We propose a simulation-based approach, named nifts, to calculate powers and determine the necessary sample size to achieve a desired power for non-inferiority trials that allow treatment switching, in ITT analysis using DRMST.

Results

The nifts approach offers three options for a non-inferiority margin, assumes three entry patterns and generalized gamma distributions for event ti

SUBMITTER: Shih A 

PROVIDER: S-EPMC12144734 | biostudies-literature | 2025 Jun

REPOSITORIES: biostudies-literature