## Statistical Science

### Bayesian Statistics and the Efficiency and Ethics of Clinical Trials

Donald A. Berry

#### Abstract

The Bayesian approach is being used increasingly in medical research. The flexibility of the Bayesian approach allows for building designs of clinical trials that have good properties of any desired sort. Examples include maximizing effective treatment of patients in the trial, maximizing information about the slope of a dose–response curve, minimizing costs, minimizing the number of patients treated, minimizing the length of the trial and combinations of these desiderata. They also include standard frequentist operating characteristics when these are important considerations. Posterior probabilities are updated via Bayes’ theorem on the basis of accumulating data. These are used to effect modifications of the trial’s course, including stopping accrual, extending accrual beyond that originally planned, dropping treatment arms, adding arms, etc. An important aspect of the approach I advocate is modeling the relationship between a trial’s primary endpoint and early indications of patient performance—auxiliary endpoints. This has several highly desirable consequences. One is that it improves the efficiency of adaptive trials because information is available sooner than otherwise.

#### Article information

Source
Statist. Sci., Volume 19, Number 1 (2004), 175-187.

Dates
First available in Project Euclid: 14 July 2004

https://projecteuclid.org/euclid.ss/1089808281

Digital Object Identifier
doi:10.1214/088342304000000044

Mathematical Reviews number (MathSciNet)
MR2086326

Zentralblatt MATH identifier
1057.62096

#### Citation

Berry, Donald A. Bayesian Statistics and the Efficiency and Ethics of Clinical Trials. Statist. Sci. 19 (2004), no. 1, 175--187. doi:10.1214/088342304000000044. https://projecteuclid.org/euclid.ss/1089808281

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