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Directional Tests for the Analysis of Clinical Trials with Multiple Endpoints Allowing for Incomplete Data
Author(s) -
Bregenzer Thomas,
Lehmacher Walter
Publication year - 1998
Publication title -
biometrical journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.108
H-Index - 63
eISSN - 1521-4036
pISSN - 0323-3847
DOI - 10.1002/(sici)1521-4036(199812)40:8<911::aid-bimj911>3.0.co;2-w
Subject(s) - missing data , nonparametric statistics , parametric statistics , multivariate statistics , computer science , data mining , multivariate analysis , statistics , type i and type ii errors , mathematics , algorithm
Incomplete data are a serious problem in the multivariate analysis of clinical trials. Usually a complete‐case analysis is performed: All incomplete observation vectors are excluded from the analysis. Provided that observations are missing randomly, an easy‐to‐handle available‐case analysis is introduced, allowing the analysis of all data without insertion or deletion of observations. This method is applied to parametric and nonparametric test procedures of the O'Brien type, which are more powerful than the conventional Hotelling's T 2 for detecting alternatives where the (treatment) effect has the same direction for all observed variables. In addition, the applicability of these so‐called directional tests, especially in the case of small samples, and their pros and cons are discussed.