, Volume 17, Issue 4, pp 339–349 | Cite as

Inference for the Cost-Effectiveness Acceptability Curve and Cost-Effectiveness Ratio

  • Anthony O’Hagan
  • John W. Stevens
  • Jacques Montmartin
Review Article


The aim of this article is to consider Bayesian and frequentist inference methods for measures of incremental cost effectiveness in data obtained via a clinical trial. The most useful measure is the cost-effectiveness (C/E) acceptability curve. Recent publications on Bayesian estimation have assumed a normal posterior distribution, which ignores uncertainty in estimated variances, and suggest unnecessarily complicated methods of computation. We present a simple Bayesian computation for the C/E acceptability curve and a simple frequentist analogue. Our approach takes account of errors in estimated variances, resulting in calculations that are based on distributions rather than normal distributions.

If inference is required about theC/E ratio,we argue that the standard frequentist procedures give unreliable or misleading inferences, and present instead a Bayesian interval.


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Copyright information

© Adis International Limited 2000

Authors and Affiliations

  • Anthony O’Hagan
    • 1
  • John W. Stevens
    • 2
  • Jacques Montmartin
    • 2
  1. 1.Statistical Services UnitUniversity of SheffieldSheffieldEngland
  2. 2.Astra CharnwoodLoughborough, LeicestershireEngland

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