June 09, 2026

Understanding and Mitigating Endpoint Bias in External Control Arms

28 minutes

A Conversation with Benjamin Ackerman

External control arms are becoming increasingly important in drug development, but creating valid comparisons requires more than matching patient populations.

In this episode, I speak with Ben Ackerman, Director of Real-World Biostatistics at GSK, about one of the most overlooked challenges in external control arm studies: endpoint bias. We discuss why differences in how outcomes are measured can influence study results, what researchers should consider when designing studies, and how the field is evolving to address these challenges.

If you work with real-world evidence, causal inference, or innovative clinical trial designs, this episode offers valuable insights into improving the credibility and transparency of external control arm analyses.

**Why You Should Listen

Learn why endpoint alignment matters as much as population matching.

Understand how measurement differences can create bias in external control arm studies.

Discover practical methods to quantify and mitigate endpoint bias.

Hear how regulators are increasingly evaluating endpoint comparability.

Gain insights into better study design and pre-specification strategies for real-world evidence research.

**Episode Highlights

00:01:31 – Introducing Ben Ackerman and external control arms

00:04:41 – Why endpoint bias deserves more attention

00:08:38 – Understanding the challenges of comparing different data sources

00:12:30 – Practical considerations for study design

00:16:32 – The role of transparency and pre-specification

00:20:30 – Regulatory perspectives and future expectations

00:26:07 – Where the field is heading next

**About Ben Ackerman

Ben Ackerman is Director of Real-World Biostatistics at GSK and a PhD biostatistician specializing in causal inference, real-world evidence methods, and the integration of randomized trial data with observational data sources. His research focuses on improving evidence generation through innovative statistical methods that bridge clinical trials and real-world healthcare data.

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By Alexander Schacht and Benjamin Piske, biometricians, statisticians and leaders in the pharma industry

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