Preface xi
1 Concepts 1
1.1 Introduction 1
1.2 Cost-effectiveness data and the parameters of interest 2
1.3 The cost-effectiveness plane, the ICER and INB 5
1.4 Outline 8
2 Parameter Estimation for Non-censored Data 11
2.1 Introduction 11
2.2 Cost 12
2.2.1 Sample means for estimating incremental cost 12
2.2.2 Using multiple regression models 14
2.2.3 Transformation (and the retransformation problem) 15
2.2.4 Generalized linear models 17
2.2.5 Two-part models for excess zeros 18
2.2.6 Cost prediction models 19
2.3 Effectiveness 20
2.3.1 Probability of surviving 21
2.3.2 Mean survival time 21
2.3.3 Mean quality-adjusted survival time 22
2.3.4 Mean quality-adjusted survival: controlling for baseline utility 24
2.4 Summary 25
3 Parameter Estimation for Censored Data 27
3.1 Introduction 27
3.2 Mean Cost 28
3.2.1 Direct (Lin) method 29
3.2.2 Inverse-probability weighting 31
3.3 Effectiveness 34
3.3.1 Probability of surviving 34
viii Contents
3.3.2 Mean survival time 36
3.3.3 Mean quality-adjusted survival time 39
3.4 Summary 42
4 Cost-effectiveness Analysis 43
4.1 Introduction 43
4.2 Incremental cost-effectiveness ratio 44
4.3 Incremental net benefit 49
4.4 The cost-effectiveness acceptability curve 51
4.5 Using bootstrap methods 54
4.6 A Bayesian incremental net benefit approach 57
4.7 Kinked thresholds 60
4.8 Summary 64
5 Cost-effectiveness Analysis: Examples 67
5.1 Introduction 67
5.2 The CADET-Hp trial 67
5.3 Symptomatic hormone-resistant prostate cancer 72
5.4 The Canadian implantable defibrillator study (CIDS) 77
5.5 The EVALUATE trial 82
5.6 Bayesian approach applied to the UK PDS study 86
5.7 Summary 90
6 Power and Sample Size Determination 93
6.1 Introduction 93
6.2 Approaches based on the cost-effectiveness plane 94
6.2.1 Briggs and Gray 95
6.2.2 Willan and O’Brien 98
6.2.3 Gardiner et al. 101
6.3 The classical approach based on net benefit 103
6.3.1 The method 103
6.3.2 Example 105
6.4 Bayesian take on the classical approach 106
6.4.1 The Method 106
6.4.2 Example 107
6.5 The value of information approach 108
6.5.1 The method 108
6.5.2 Example 114
6.6 Summary 116
7 Covariate Adjustment and Sub-group Analysis 117
7.1 Introduction 117
7.2 Non-censored data 118
7.2.1 Example, non-censored data 121
Contents ix
7.3 Censored data 129
7.3.1 Cost 131
7.3.2 Quality-adjusted survival time 132
7.3.3 Survival time 134
7.3.4 The Canadian implantable defibrillator study (CIDS) 135
7.3.5 The evaluate trial 138
7.4 Summary 142
8 Multicenter and Multinational Trials 145
8.1 Introduction 145
8.2 Background to multinational cost-effectiveness 147
8.3 Fixed effect approaches 151
8.3.1 Willke et al. 151
8.3.2 Cook et al. 152
8.4 Random effects approaches 154
8.4.1 Aggregate level analysis: multicenter trials 154
8.4.2 Aggregate level analysis: multinational trials 156
8.4.3 Hierarchical modeling 162
8.5 Summary 164
9 Modeling Cost-effectiveness 165
9.1 Introduction 165
9.2 A general framework for modeling cost-effectiveness results 166
9.3 Case study: an economic appraisal of the goal study 167
9.3.1 The GOAL study 168
9.3.2 Standard approach to estimating cost-effectiveness 170
9.3.3 An alternative approach to estimating cost-effectiveness 171
9.3.4 Comparing the two analyses of GOAL 179
9.4 Summary 180
References 183
Author Index 193
Subject Index 195
Series List 197