Table of contents : Preface Contents Part IBasics 1 Introduction 1.1 Background and Overview 1.2 Examples 1.2.1 The ChroPac Trial 1.2.2 The Parkinson Trial 1.3 General Considerations When Calculating Sample Sizes 2 Statistical Test and Sample Size Calculation 2.1 The Main Principle of Statistical Testing 2.2 The Main Principle of Sample Size Calculation Part IISample Size Calculation 3 Comparison of Two Groups for Normally Distributed Outcomes and Test for Difference or Superiority 3.1 Background and Notation 3.2 z-Test 3.3 t-Test 3.4 Analysis of Covariance 3.5 Bayesian Approach 3.5.1 Background 3.5.2 Methods 4 Comparison of Two Groups for Continuous and Ordered Categorical Outcomes and Test for Difference or Superiority 4.1 Background and Notation 4.2 Continuous Outcomes 4.3 Ordered Categorical Outcomes 4.3.1 Assumption-Free Approach 4.3.2 Assuming Proportional Odds 5 Comparison of Two Groups for Binary Outcomes and Test for Difference or Superiority 5.1 Background and Notation 5.2 Asymptotic Tests 5.2.1 Difference of Rates as Effect Measure 5.2.2 Risk Ratio as Effect Measure 5.2.3 Odds Ratio as Effect Measure 5.2.4 Logistic Regression 5.3 Exact Unconditional Tests 5.3.1 Basic Concepts 5.3.2 Fisher-Boschloo Test 6 Comparison of Two Groups for Time-to-Event Outcomes and Test for Difference or Superiority 6.1 Background and Notation 6.1.1 Time-to-Event Data 6.1.2 Sample Size Calculation for Time-to-Event Data 6.2 Exponentially Distributed Time-to-Event Data 6.3 Time-to-Event Data with Proportional Hazards 6.3.1 Approach of Schoenfeld 6.3.2 Approach of Freedman 7 Comparison of More Than Two Groups and Test for Difference 7.1 Background and Notation 7.2 Normally Distributed Outcomes 7.3 Continuous Outcomes 7.4 Binary Outcomes 7.4.1 Chi-Square Test 7.4.2 Cochran-Armitage Test 7.5 Time-to-Event Outcomes 8 Comparison of Two Groups and Test for Non-Inferiority 8.1 Background and Notation 8.2 Normally Distributed Outcomes 8.2.1 Difference of Means as Effect Measure 8.2.2 Ratio of Means as Effect Measure 8.3 Continuous and Ordered Categorical Outcomes 8.4 Binary Outcomes 8.4.1 Asymptotic Tests 8.4.2 Exact Unconditional Tests 8.5 Time-to-Event Outcomes 9 Comparison of Three Groups in the Gold Standard Non-Inferiority Design 9.1 Background and Notation 9.2 Net Effect Approach 9.3 Fraction Effect Approach 10 Comparison of Two Groups for Normally Distributed Outcomes and Test for Equivalence 10.1 Background and Notation 10.2 Difference of Means as Effect Measure 10.3 Ratio of Means as Effect Measure 11 Multiple Comparisons 11.1 Background and Notation 11.2 Generally Applicable Sample Size Calculation Methods and Applications 11.2.1 Methods 11.2.2 Applications 11.3 Multiple Endpoints 11.3.1 Background and Notation 11.3.2 Methods 11.4 More Than Two Groups 11.4.1 Background and Notation 11.4.2 Dunnett Test 12 Assessment of Safety 12.1 Background and Notation 12.2 Testing Hypotheses on the Event Probability 12.2.1 Exact Binomial Test 12.2.2 Approximate Score Test 12.3 Estimating the Event Probability with Specified Precision 12.3.1 Exact Clopper-Pearson Confidence Interval 12.3.2 Approximate Wilson Score Confidence Interval 12.4 Observing at Least One Event with Specified Probability 13 Cluster-Randomized Trials 13.1 Background and Notation 13.2 Normally Distributed Outcomes 13.2.1 Cluster-Level Analysis 13.2.2 Individual-Level Analysis 13.2.3 Dealing with Unequal Cluster Size 13.3 Other Scale Levels of the Outcome 14 Multi-Regional Trials 14.1 Background and Notation 14.2 Demonstrating Consistency of Global Results and Results for a Specified Region 14.3 Demonstrating a Consistent Trend Across All Regions 15 Integrated Planning of Phase II/III Drug Development Programs 15.1 Background and Notation 15.2 Optimizing Phase II/III Programs 16 Simulation-Based Sample Size Calculation Part IIISample Size Recalculation 17 Basic Concepts of Sample Size Recalculation Part IVBlinded Sample Size Recalculation in Internal Pilot Study Designs 18 Internal Pilot Study Designs 19 A General Approach for Controlling the Type I Error Rate for Blinded Sample Size Recalculation 20 Comparison of Two Groups for Normally Distributed Outcomes and Test for Difference or Superiority 20.1 t-Test 20.1.1 Background and Notation 20.1.2 Blinded Sample Size Recalculation 20.1.3 Type I Error Rate 20.1.4 Power and Sample Size 20.2 Analysis of Covariance 20.2.1 Background and Notation 20.2.2 Blinded Sample Size Recalculation 20.2.3 Type I Error Rate 20.2.4 Power and Sample Size 21 Comparison of Two Groups for Binary Outcomes and Test for Difference or Superiority 21.1 Background and Notation 21.2 Asymptotic Tests 21.2.1 Difference of Rates as Effect Measure 21.2.2 Risk Ratio or Odds Ratio as Effect Measure 21.3 Fisher-Boschloo Test 22 Comparison of Two Groups for Normally Distributed Outcomes and Test for Non-Inferiority 22.1 t-Test 22.1.1 Background and Notation 22.1.2 Blinded Sample Size Recalculation 22.1.3 Type I Error Rate 22.1.4 Power and Sample Size 22.2 Analysis of Covariance 23 Comparison of Two Groups for Binary Outcomes and Test for Non-Inferiority 23.1 Background and Notation 23.2 Difference of Rates as Effect Measure 23.2.1 Blinded Sample Size Recalculation 23.2.2 Type I Error Rate 23.2.3 Power and Sample Size 23.3 Risk Ratio or Odds Ratio as Effect Measure 24 Comparison of Two Groups for Normally Distributed Outcomes and Test for Equivalence 25 Regulatory and Operational Aspects 26 Concluding Remarks Part VUnblinded Sample Size Recalculation in Adaptive Designs 27 Group Sequential and Adaptive Designs 27.1 Group Sequential Designs 27.2 Adaptive Designs 27.2.1 Combination Function Approach 27.2.2 Conditional Error Function Approach 28 Sample Size Recalculation Based on Conditional Power 28.1 Background and Notation 28.2 Using the Interim Effect Estimate 28.3 Using the Initially Specified Effect 28.4 Using Prior Information as Well as the Interim Effect Estimate 29 Sample Size Recalculation Based on Optimization 30 Regulatory and Operational Aspects 31 Concluding Remarks Appendix R Software Code A.1 Output of Sample Size Functions A.2 Remarks on the Rounding Strategy A.3 R Code for Chapter 3 A.4 R Code for Chapter 4 A.5 R Code for Chapter 5 A.6 R Code for Chapter 6 A.7 R Code for Chapter 7 A.8 R Code for Chapter 8 A.9 R Code for Chapter 9 A.10 R Code for Chapter 10 A.11 R Code for Chapter 11 A.12 R Code for Chapter 12 A.13 R Code for Chapter 13 A.14 R Code for Chapter 14 A.15 R Code for Chapter 15 A.16 R Code for Chapter 20 A.17 R Code for Chapter 21 A.18 R Code for Chapter 22 A.19 R Code for Chapter 23 A.20 R Code for Chapter 27 A.21 R Code for Chapter 28 A.22 R Code for Chapter 29 References Index