1. Division of Biometrics III, Office of Biostatistics; OTS, CDER, FDA; Silver Spring MD 20993 U.S.A.
2. Office of Biostatistics; OTS, CDER, FDA; Silver Spring MD 20993 U.S.A.
3. Statistical Methodology and Consulting; Novartis; Basel Switzerland
4. Center for Medical Statistics, Informatics and Intelligent Systems; Medical University of Vienna; Wien Austria
5. Mathematics and Statistics Department; Boston University; Boston MA U.S.A.