Implementing a Mid-Trial Adaptation in a Stroke Clinical Trial: The Good, The Bad and the Ugly

The use of adaptive designs has been increasing in randomized clinical trials. Sample size re-estimation is a type of adaptation in which nuisance parameters are estimated at an interim point in the trial and the sample size re-computed based on these estimates. However, post-hoc evaluations of the adaptation, including sample size re-estimation, have not frequently been performed, leaving open questions about the gains that come from utilizing these procedures in practice. In this talk, I discuss the impact of a sample size re-estimation that was implemented in the Secondary Prevention of Small Subcortical Strokes (SPS3) study, both on the statistical properties of the study, as well as the practical study aspects.

Dr. McClure is Professor & Chair of the Department of Epidemiology and Biostatistics at the Dornsife School of Public Health at Drexel University. She is a clinical trials biostatistician by training and is interested in the design, implementation and methodology behind multi-center trials. Dr. McClure also has interests in the impact of the environment on the risk of chronic diseases. She has over 150 peer-reviewed publications and has been recognized for her outstanding teaching and mentoring.

The Innovative Discoveries Series, sponsored by the Delaware Clinical & Translational Science ACCEL program and the Christiana Care Value Institute, features informal presentations on topics relevant to current research and healthcare practice, led by knowledgeable and experienced presenters. There are offerings for researchers, healthcare providers, and community members of varying levels of experience.

These free talks are held Fridays at noon at Christiana Hospital but can be viewed from your home or office computer. Earn CMEs by participating in-person or online. Lunch is served and all are welcome to attend.

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  • Leslie McClure, PhD