Manju, Md Abu; Candel, Math J. J. M.; van Breukelen, Gerard J. P. SamP2Cet: an interactive computer program for sample size and power calculation for two-level cost-effectiveness trials. (English) Zbl 1417.62008 Comput. Stat. 34, No. 1, 47-70 (2019). Summary: The cost-effectiveness of interventions (e.g. new medical therapies or health care technologies) is often evaluated in randomized clinical trials, where individuals are nested within clusters, for instance patients within general practices. In such two-level cost-effectiveness trials, one can randomly assign treatments to individuals within clusters (multicentre trial) or to entire clusters (cluster randomized trial). Such trials need careful planning to evaluate the cost-effectiveness of interventions within the available research resources. The optimal number of clusters and the optimal number of subjects per cluster for both types of cost-effectiveness trials can be determined by using optimal design theory. However, the construction of the optimal design requires information on model parameters, which may be unknown at the planning stage of a trial. To overcome this problem, a maximin strategy is employed. We have developed a computer program SamP2CeT in R to perform these sample size calculations. SamP2CeT provides a graphical user interface which enables the researchers to optimize the numbers of clusters and subjects per cluster in their cost-effectiveness trial as a function of study costs and outcome variances. In case of insufficient knowledge on model parameters, SamP2CeT also provides safe numbers of clusters and subjects per cluster, based on a maximin strategy. SamP2CeT can be used to calculate the smallest budget needed for a user-specified power level, the largest power attainable with a user-specified budget, and also has the facility to calculate the power for a user-specified design. Recent methodological developments on sample size and power calculation for two-level cost-effectiveness trials have been implemented in SamP2CeT. This program is user-friendly, as illustrated for two published cost-effectiveness trials. Cited in 1 Document MSC: 62-04 Software, source code, etc. for problems pertaining to statistics 62P10 Applications of statistics to biology and medical sciences; meta analysis Keywords:cluster randomized trials; cost-effectiveness analysis; maximin design; multicentre trials; optimal design; power; sample size calculation Software:R; SAS; tcltk; SamP2Cet; PinT; MCPMod PDFBibTeX XMLCite \textit{M. A. Manju} et al., Comput. Stat. 34, No. 1, 47--70 (2019; Zbl 1417.62008) Full Text: DOI References: [1] Atkinson AC, Donev AN, Tobias RD (2007) Optimum experimental designs, with SAS. Oxford University Press, Oxford · Zbl 1183.62129 [2] Berger MPF, Wong WK (2009) An introduction to optimal designs for social and bio-medical research. 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