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Updated: Jul 9, 2026
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Preparation and Analysis of In Vitro Three Dimensional Breast Carcinoma Surrogates
Published on: May 9, 2016
Information-theory based surrogate marker evaluation from several randomized clinical trials with continuous true and
Assam Pryseley1, Abel Tilahun, Ariel Alonso
1Hasselt University, Center for Statistics, Agoralaan 1, B3590 Diepenbeek, Belgium.
Clinical Trials (London, England)
|November 29, 2007
Summary
A new information-theoretic approach offers a computationally efficient alternative for evaluating surrogate endpoints in clinical trials. This method is recommended for large trials, showing promise but not overwhelming potential for vision loss endpoints.
Area of Science:
- Biostatistics
- Clinical Trial Design
- Health Economics
Background:
- Surrogate endpoints can shorten study duration and reduce costs.
- They may improve research reliability by addressing noncompliance and missing data.
- This study evaluates methods for assessing surrogate endpoint validity.
Purpose of the Study:
- Review meta-analytic approaches for surrogate endpoints.
- Extend these methods to mixed continuous and binary outcomes.
- Propose and evaluate an information-theoretic alternative.
Main Methods:
- The study reviews existing meta-analytic methods (Buyse et al., Molenberghs, Buyse).
- An information-theoretic approach (Alonso and Molenberghs) is proposed.
- Simulations and an ophthalmologic trial dataset were used for evaluation, with an R function implemented.
Main Results:
- The information-theoretic approach is theoretically sound and easy to apply.
- It exhibits desirable properties by focusing on observed outcomes.
- A slight downward bias was noted, attributed to not using latent scales.
Conclusions:
- The information-theoretic approach is a viable, computationally less expensive alternative to meta-analysis.
- It is recommended for large trials due to potential bias in smaller ones.
- In ophthalmology, 6-month vision loss shows limited promise as a surrogate for 12-month outcomes.
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