Power and sample size in cost-effectiveness analysis.
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.
Laska
E M
EM
Statistical Sciences and Epidemiology Division of The Nathan S. Kline Institute for Psychiatric Research, Orangeburg, New York 10962, USA. laska@nki.rfmh.org
Meisner
M
M
Siegel
C
C
D015982:Bias; D003362:Cost-Benefit Analysis / Q000706:statistics & numerical data*; D003627:Data Interpretation, Statistical; D003661:Decision Support Techniques; D015276:Health Care Rationing / Q000191:economics*; D006801:Humans