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Considerations on the statistical design of the ATMI study
R Eisebitt1, W Lehmacher, R Lefering
1Inst. for Numerical Statistics IFNS GmbH, Cologne, Germany.
Abstract:
The ATMI study of prevention of mediastinitis after cardiac surgery uses the total amount of therapeutic interventions measured by the TISS-28 score as the primary endpoint. The study is designed as an adaptive group-sequential plan with three sequences, as experiences with the TISS-28 in cardiac intensive care units are scarce. According to the Bauer-Köhne method the sample sizes of the second and third sequences can be calculated in a data-driven manner after the results of the previous interim analyses are available. Thus the first trial phase can be considered as an internal pilot study.
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