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PharmacoEconomics
Published in: PharmacoEconomics 11/2011

01-11-2011 | Practical Application

Sample Size Determination for Cost-Effectiveness Trials

Author: Dr Andrew R. Willan

Published in: PharmacoEconomics | Issue 11/2011

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Abstract

Methods for determining sample size requirements for cost-effectiveness studies are reviewed and illustrated. Traditional methods based on tests of hypothesis and power arguments are given for the incremental costeffectiveness ratio and incremental net benefit (INB). In addition, a full Bayesian approach using decision theory to determine optimal sample size is given for INB. The full Bayesian approach, based on the value of information, is proposed in reaction to concerns that traditional methods rely on arbitrarily chosen error probabilities and an ill-defined notion of the smallest clinically important difference. Furthermore, the results of cost-effectiveness studies are used for decision making (e.g. should a new intervention be adopted or the old one retained), and employing decision theory, which permits optimal use of current information and the optimal design of new studies, provides a more consistent approach.
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Metadata
Title
Sample Size Determination for Cost-Effectiveness Trials
Author
Dr Andrew R. Willan
Publication date
01-11-2011
Publisher
Springer International Publishing
Published in
PharmacoEconomics / Issue 11/2011
Print ISSN: 1170-7690
Electronic ISSN: 1179-2027
DOI
https://doi.org/10.2165/11587130-000000000-00000

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