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1.1 What are Bayesian methods? |
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1.2 What do we mean by ‘health-care evaluation’? |
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1.3 A Bayesian approach to evaluation. |
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1.4 The aim of this book and the intended audience. |
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1.5 Structure of the book. |
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2 Basic Concepts from Traditional Statistical Analysis. |
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2.1.1 What is probability? |
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2.1.3 Bayes theorem for simple events. |
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2.2 Random variables, parameters and likelihood. |
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2.2.1 Random variables and their distributions. |
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2.2.2 Expectation, variance, covariance and correlation. |
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2.2.3 Parametric distributions and conditional independence. |
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2.3 The normal distribution. |
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2.4.1 Normal approximations for binary data. |
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2.4.2 Normal likelihoods for survival data. |
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2.4.3 Normal likelihoods for count responses. |
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2.4.4 Normal likelihoods for continuous responses. |
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2.6 A catalogue of useful distributions*. |
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2.6.1 Binomial and Bernoulli. |
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2.6.6 Root-inverse-gamma. |
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3 An Overview of the Bayesian Approach. |
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3.1 Subjectivity and context. |
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3.2 Bayes theorem for two hypotheses. |
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3.3 Comparing simple hypotheses: likelihood ratios and Bayes factors. |
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3.4 Exchangeability and parametric modelling*. |
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3.5 Bayes theorem for general quantities. |
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3.6 Bayesian analysis with binary data. |
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3.6.1 Binary data with a discrete prior distribution. |
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3.6.2 Conjugate analysis for binary data. |
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3.7 Bayesian analysis with normal distributions. |
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3.8 Point estimation, interval estimation and interval hypotheses. |
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3.9 The prior distribution. |
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3.10 How to use Bayes theorem to interpret trial results. |
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3.11 The ‘credibility’ of significant trial results*. |
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3.12 Sequential use of Bayes theorem*. |
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3.13.1 Predictions in the Bayesian framework. |
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3.13.2 Predictions for binary data*. |
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3.13.3 Predictions for normal data. |
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3.16 Use of historical data. |
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3.17 Multiplicity, exchangeability and hierarchical models. |
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3.18 Dealing with nuisance parameters*. |
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3.18.1 Alternative methods for eliminating nuisance parameters*. |
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3.18.2 Profile likelihood in a hierarchical model*. |
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3.19 Computational issues. |
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3.19.1 Monte Carlo methods. |
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3.19.2 Markov chain Monte Carlo methods. |
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3.20 Schools of Bayesians. |
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3.21 A Bayesian checklist. |
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4 Comparison of Alternative Approaches to Inference. |
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4.1 A structure for alternative approaches. |
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4.2 Conventional statistical methods used in health-care evaluation. |
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4.3 The likelihood principle, sequential analysis and types of error. |
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4.3.1 The likelihood principle. |
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4.3.2 Sequential analysis. |
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4.3.3 Type I and Type II error. |
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4.4 P-values and Bayes factors*. |
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4.4.1 Criticism of P-values. |
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4.4.2 Bayes factors as an alternative to P-values: simple hypotheses. |
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4.4.3 Bayes factors as an alternative to P-values: composite hypotheses. |
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4.4.4 Bayes factors in preference studies. |
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5.2 Elicitation of opinion: a brief review. |
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5.2.1 Background to elicitation. |
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5.2.2 Elicitation techniques. |
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5.2.3 Elicitation from multiple experts. |
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5.3 Critique of prior elicitation. |
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5.4 Summary of external evidence*. |
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5.5.1 ‘Non-informative’ or ‘reference’ priors: |
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5.5.2 ‘Sceptical’ priors. |
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5.5.3 ‘Enthusiastic’ priors. |
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5.5.4 Priors with a point mass at the null hypothesis (‘lump-and-smear’ priors)*. |
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5.6 Sensitivity analysis and ‘robust’ priors. |
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5.7.1 The judgement of exchangeability. |
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5.7.2 The form for the random-effects distribution. |
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5.7.3 The prior for the standard deviation of the random effects*. |
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5.8 Empirical criticism of priors. |
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6 Randomised Controlled Trials. |
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6.2 Use of a loss function: is a clinical trial for inference or decision? |
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6.3 Specification of null hypotheses. |
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6.4 Ethics and randomisation: a brief review. |
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6.4.1 Is randomisation necessary? |
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6.4.2 When is it ethical to randomise? |
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6.5 Sample size of non-sequential trials. |
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6.5.1 Alternative approaches to sample-size assessment. |
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6.5.2 ‘Classical power’: hybrid classical-Bayesian methods assuming normality. |
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6.5.4 Adjusting formulae for different hypotheses. |
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6.5.5 Predictive distribution of power and necessary sample size. |
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6.6 Monitoring of sequential trials. |
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6.6.2 Monitoring using the posterior distribution. |
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6.6.3 Monitoring using predictions: ‘interim power’. |
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6.6.4 Monitoring using a formal loss function. |
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6.6.5 Frequentist properties of sequential Bayesian methods. |
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6.6.6 Bayesian methods and data monitoring committees. |
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6.7 The role of ‘scepticism’ in confirmatory studies. |
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6.8 Multiplicity in randomised trials. |
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6.8.2 Multi-centre analysis. |
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6.8.3 Cluster randomization. |
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6.8.4 Multiple endpoints and treatments. |
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6.9 Using historical controls*. |
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6.10 Data-dependent allocation. |
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6.11 Trial designs other than two parallel groups. |
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6.12 Other aspects of drug development. |
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7.2 Alternative study designs. |
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7.3 Explicit modelling of biases. |
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7.4 Institutional comparisons. |
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8.2 ‘Standard’ meta-analysis. |
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8.2.1 A Bayesian perspective. |
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8.2.2 Some delicate issues in Bayesian meta-analysis. |
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8.2.3 The relationship between treatment effect and underlying risk. |
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8.3 Indirect comparison studies. |
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8.4 Generalised evidence synthesis. |
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9 Cost-effectiveness, Policy-Making and Regulation. |
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9.3 ‘Standard’ cost-effectiveness analysis without uncertainty. |
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9.4 ‘Two-stage’ and integrated approaches to uncertainty in cost-effectiveness modeling. |
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9.5 Probabilistic analysis of sensitivity to uncertainty about parameters: two-stage approach. |
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9.6 Cost-effectiveness analyses of a single study: integrated approach. |
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9.7 Levels of uncertainty in cost-effectiveness models. |
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9.8 Complex cost-effectiveness models. |
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9.8.1 Discrete-time, discrete-state Markov models. |
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9.8.2 Micro-simulation in cost-effectiveness models. |
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9.8.3 Micro-simulation and probabilistic sensitivity analysis. |
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9.8.4 Comprehensive decision modeling. |
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9.9 Simultaneous evidence synthesis and complex cost-effectiveness modeling. |
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9.9.1 Generalised meta-analysis of evidence. |
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9.9.2 Comparison of integrated Bayesian and two-stage approach. |
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9.10 Cost-effectiveness of carrying out research: payback models. |
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9.10.1 Research planning in the public sector. |
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9.10.2 Research planning in the pharmaceutical industry. |
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9.10.3 Value of information. |
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9.11 Decision theory in cost-effectiveness analysis, regulation and policy. |
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9.12 Regulation and health policy. |
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9.12.1 The regulatory context. |
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9.12.2 Regulation of pharmaceuticals. |
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9.12.3 Regulation of medical devices. |
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10 Conclusions and Implications for Future Research. |
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10.2 General advantages and problems of a Bayesian approach. |
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10.3 Future research and development. |
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A.1 The site for this book. |
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A.2 Bayesian methods in health-care evaluation. |
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A.4 General Bayesian sites. |
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