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PubMed · 10424840

Power and sample size in cost-effectiveness analysis.

E M Laska·M Meisner·C Siegel
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Abstract

For resource allocation under a constrained budget, optimal decision rules for mutually exclusive programs require that the treatment with the highest incremental cost-effectiveness ratio (ICER) below a willingness-to-pay (WTP) criterion be funded. This is equivalent to determining the treatment with the smallest net health cost. The designer of a cost-effectiveness study needs to select a sample size so that the power to reject the null hypothesis, the equality of the net health costs of two treatments, is high. A recently published formula derived under normal distribution theory overstates sample-size requirements. Using net health costs, the authors present simple methods for power analysis based on conventional normal and on nonparametric statistical theory.

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BiasCost-Benefit AnalysisData Interpretation, StatisticalDecision Support TechniquesHealth Care RationingHumansJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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E M Laska, M Meisner, C Siegel. Power and sample size in cost-effectiveness analysis.. https://doi.org/10.1177/0272989x9901900312

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