F Bretz

Summary

Affiliation: Novartis Institutes for BioMedical Research

Publications

  1. ncbi Detecting dose-response using contrasts: asymptotic power and sample size determination for binomial data
    Frank Bretz
    Research Unit Bioinformatics, University of Hannover, Herrenhauser Str 2, 30419 Hannover, Germany
    Stat Med 21:3325-35. 2002
  2. ncbi Power and sample size computations in simultaneous tests for non-inferiority based on relative margins
    Gemechis Dilba
    Bioinformatics Unit, University of Hannover, Germany
    Stat Med 25:1131-47. 2006
  3. ncbi Confirmatory seamless phase II/III clinical trials with hypotheses selection at interim: general concepts
    Frank Bretz
    Novartis Pharma AG, Lichtstrasse 35, 4002 Basel, Switzerland
    Biom J 48:623-34. 2006
  4. ncbi Power and sample size when multiple endpoints are considered
    Stephen Senn
    Department of Statistics, University of Glasgow, Glasgow, Scotland, UK
    Pharm Stat 6:161-70. 2007
  5. pmc Adaptive designs based on the truncated product method
    Markus Neuhauser
    Institute for Medical Informatics, Biometry and Epidemiology, University of Duisburg Essen, Hufelandstr 55, D 45122 Essen, Germany
    BMC Med Res Methodol 5:30. 2005
  6. pmc Graphical approaches for multiple comparison procedures using weighted Bonferroni, Simes, or parametric tests
    Frank Bretz
    Statistical Methodology, Novartis Pharma AG, Basel, Switzerland
    Biom J 53:894-913. 2011
  7. ncbi Combining multiple comparisons and modeling techniques in dose-response studies
    F Bretz
    Novartis Pharma AG, Lichtstrasse 35, Basel, Switzerland
    Biometrics 61:738-48. 2005
  8. ncbi Multiplicity issues in microarray experiments
    F Bretz
    B and SR, Novartis Pharma AG, Lichtstr 35, 4002 Basel, Switzerland
    Methods Inf Med 44:431-7. 2005
  9. doi Dose finding - a challenge in statistics
    Frank Bretz
    Clinical Information Sciences, Novartis Pharma AG, CH 4002 Basel, Switzerland
    Biom J 50:480-504. 2008
  10. doi Practical considerations for optimal designs in clinical dose finding studies
    Frank Bretz
    Novartis Pharma AG, CH 4002 Basel, Switzerland
    Stat Med 29:731-42. 2010

Detail Information

Publications25

  1. ncbi Detecting dose-response using contrasts: asymptotic power and sample size determination for binomial data
    Frank Bretz
    Research Unit Bioinformatics, University of Hannover, Herrenhauser Str 2, 30419 Hannover, Germany
    Stat Med 21:3325-35. 2002
    ..Some numerical results of a power study for small to moderate sample sizes show that the nominal power is a reasonably good approximation to the actual power. An example from a clinical trial illustrates the practical use of the results...
  2. ncbi Power and sample size computations in simultaneous tests for non-inferiority based on relative margins
    Gemechis Dilba
    Bioinformatics Unit, University of Hannover, Germany
    Stat Med 25:1131-47. 2006
    ..The results are illustrated with examples...
  3. ncbi Confirmatory seamless phase II/III clinical trials with hypotheses selection at interim: general concepts
    Frank Bretz
    Novartis Pharma AG, Lichtstrasse 35, 4002 Basel, Switzerland
    Biom J 48:623-34. 2006
    ..In a subsequent paper (Schmidli et al., 2006) we give several applications from our daily practice and discuss related implementation issues in conducting adaptive seamless designs...
  4. ncbi Power and sample size when multiple endpoints are considered
    Stephen Senn
    Department of Statistics, University of Glasgow, Glasgow, Scotland, UK
    Pharm Stat 6:161-70. 2007
    ..We conduct a numerical study and conclude again that power is not reduced as the number of tested variables increases...
  5. pmc Adaptive designs based on the truncated product method
    Markus Neuhauser
    Institute for Medical Informatics, Biometry and Epidemiology, University of Duisburg Essen, Hufelandstr 55, D 45122 Essen, Germany
    BMC Med Res Methodol 5:30. 2005
    ..Adaptive designs are becoming increasingly important in clinical research. One approach subdivides the study into several (two or more) stages and combines the p-values of the different stages using Fisher's combination test...
  6. pmc Graphical approaches for multiple comparison procedures using weighted Bonferroni, Simes, or parametric tests
    Frank Bretz
    Statistical Methodology, Novartis Pharma AG, Basel, Switzerland
    Biom J 53:894-913. 2011
    ..We illustrate the extended graphical approaches with several examples. In addition, we describe briefly the gMCP package in R, which implements some of the methods described in this paper...
  7. ncbi Combining multiple comparisons and modeling techniques in dose-response studies
    F Bretz
    Novartis Pharma AG, Lichtstrasse 35, Basel, Switzerland
    Biometrics 61:738-48. 2005
    ..The selected model is then used to provide inference on adequate doses...
  8. ncbi Multiplicity issues in microarray experiments
    F Bretz
    B and SR, Novartis Pharma AG, Lichtstr 35, 4002 Basel, Switzerland
    Methods Inf Med 44:431-7. 2005
    ..Discussion of different error concepts relevant to microarray experiments. Review of some commonly used multiple testing procedures. Comparison of different approaches as applied to gene expression data...
  9. doi Dose finding - a challenge in statistics
    Frank Bretz
    Clinical Information Sciences, Novartis Pharma AG, CH 4002 Basel, Switzerland
    Biom J 50:480-504. 2008
    ..An outlook to adaptive dose finding methods is also given. We use a real data example to illustrate the methods, together with a brief overview of relevant software...
  10. doi Practical considerations for optimal designs in clinical dose finding studies
    Frank Bretz
    Novartis Pharma AG, CH 4002 Basel, Switzerland
    Stat Med 29:731-42. 2010
    ..Extensions to robust designs accounting for model uncertainty are also discussed. A case study is used to motivate and illustrate the methods from this paper...
  11. doi Test and power considerations for multiple endpoint analyses using sequentially rejective graphical procedures
    Frank Bretz
    Statistical Methodology, Novartis Pharma AG, Lichstr 35, CH 4002 Basel, Switzerland
    Stat Med 30:1489-501. 2011
    ..We further discuss suitable power measures for clinical trials with multiple primary and/or secondary objectives and use a generic example to illustrate our considerations...
  12. ncbi Design and analysis of two-color microarray experiments using linear models
    F Bretz
    B and SR, Novartis Pharma AG, Basel, Switzerland
    Methods Inf Med 44:423-30. 2005
    ..A variety of linear models have recently been proposed for the design and analysis of microarray experiments. This article gives an introduction to the most common models and describes their respective characteristics...
  13. ncbi On a hybrid method in dose finding studies
    F Bretz
    Novartis Pharma AG, Basel, Switzerland
    Methods Inf Med 43:457-60. 2004
    ..Estimation of target dose(s) following the previous model selection step. Illustration of the method with a real data example...
  14. doi Simultaneous confidence bands for nonlinear regression models with application to population pharmacokinetic analyses
    S Gsteiger
    Novartis Pharma AG, Basel, Switzerland
    J Biopharm Stat 21:708-25. 2011
    ..Finally, we present extensions to construct simultaneous confidence bands for the difference of two models and to assess equivalence between two models in biosimilarity applications...
  15. ncbi Innovative approaches for designing and analyzing adaptive dose-ranging trials
    Björn Bornkamp
    University of Dortmund, Dortmund, Germany
    J Biopharm Stat 17:965-95. 2007
    ....
  16. ncbi Bayesian predictive power for interim adaptation in seamless phase II/III trials where the endpoint is survival up to some specified timepoint
    Heinz Schmidli
    Novartis Pharma AG, CH 4002 Basel, Switzerland
    Stat Med 26:4925-38. 2007
    ..Frequentist properties of the adaptation criterion based on Bayesian PP are assessed by simulations...
  17. ncbi Design and analysis of dose-finding studies combining multiple comparisons and modeling procedures
    Jose Pinheiro
    Biostatistics and Statistical Reporting Department, Novartis Pharmaceuticals, East Hanover, New Jersey 07936, USA
    J Biopharm Stat 16:639-56. 2006
    ..All methods are illustrated by a real dose-response phase II study for an anti-anxiety compound...
  18. ncbi Confirmatory seamless phase II/III clinical trials with hypotheses selection at interim: applications and practical considerations
    Heinz Schmidli
    Novartis Pharma AG, Lichtstrasse 35, 4002 Basel, Switzerland
    Biom J 48:635-43. 2006
    ..Practical aspects concerning the planning and implementation of adaptive seamless confirmatory studies are also discussed...
  19. ncbi Identifying effective and/or safe doses by stepwise confidence intervals for ratios
    Frank Bretz
    Bioinformatics Unit, University of Hannover, Herrenhauser Str 2, D 30419 Hannover, Germany
    Stat Med 22:847-58. 2003
    ..The results allow sample size determination in the design phase of a study for the probability of estimating correctly the dose of interest. Auxiliary results of a numerical study show the range of application of these methods...
  20. ncbi Efficient two-sample designs for microarray experiments with biological replications
    Jobst Landgrebe
    Abteilung Medizinische Statistik, Universitat Gottingen, Heinrich Döker Weg 12, D 37073 Gottingen, Germany
    In Silico Biol 4:461-70. 2004
    ..The designs proposed in this paper can be evaluated using SAS PROC MIXED or S+/R lme...
  21. ncbi Statistical analysis of monotone or non-monotone dose-response data from in vitro toxicological assays
    Frank Bretz
    Bioinformatics Unit, University of Hannover, 30419 Hannover, Germany
    Altern Lab Anim 31:81-96. 2003
    ..New tests are introduced to overcome difficulties common to many current procedures, such as downturns at higher doses, and missing numerical availability...
  22. ncbi Dose-response and thresholds in mutagenicity studies: a statistical testing approach
    Ludwig A Hothorn
    Bioinformatics Unit, University of Hannover, 30419 Hannover, Germany
    Altern Lab Anim 31:97-103. 2003
    ..A parametric procedure is considered, together with an extension for proportions. The important problem of a priori sample size definition is discussed. The approaches are demonstrated by means of examples based on real data...
  23. doi Simultaneous inference in general parametric models
    Torsten Hothorn
    Institut für Statistik, Ludwig Maximilians Universitat Munchen, Ludwigstrasse 33, D 80539 Munchen, Germany
    Biom J 50:346-63. 2008
    ..Several examples using a variety of different statistical models illustrate the breadth of the results. For the analyses we use the R add-on package multcomp, which provides a convenient interface to the general approach adopted here...
  24. ncbi Adaptive Dunnett tests for treatment selection
    Franz Koenig
    Medical University of Vienna, Spitalgasse 23, A 1090 Wien, Austria
    Stat Med 27:1612-25. 2008
    ..The adaptive Dunnett test is compared in a simulation with the classical Dunnett test as well as with adaptive combination tests based on the closure principle. The method is illustrated with a real-data example...
  25. ncbi Powerful short-cuts for multiple testing procedures with special reference to gatekeeping strategies
    Gerhard Hommel
    University of Mainz, Mainz, Germany
    Stat Med 26:4063-73. 2007
    ..We illustrate the methodology with two real clinical studies...