High-quality evidence is the foundation for effective treatment in medicine. As the vast amount of published medical evidence continues to grow, concerns about the quality of many studies are increasing. Evidence in Medicine is a much-needed resource that addresses the ‘medical misinformation mess’ by assessing the flaws in the research environment. This authoritative text identifies and summarises the many factors that have produced the current problems in medical research, including bias in randomised controlled trials, questionable research practices, falsified data, manipulated findings, and more.
This volume brings together the findings from meta-research studies and systematic reviews to explore the quality of clinical trials and other medical research, explaining the character and consequences of poor-quality medical evidence using clear language and a wealth of supporting references. The text suggests planning strategies to transform the research process and provides an extensive list of the actions that could be taken by researchers, regulators, and other key stakeholders to address defects in medical evidence. This timely volume:
- Enables readers to select reliable studies and recognise misleading research
- Highlights the main types of biased and wasted studies
- Discusses how incentives in the research environment influence the quality of evidence
- Identifies the problems researchers need to guard against in their work
- Describes the scale of poor-quality research and explores why the problems are widespread
- Includes a summary of key findings on poor-quality research and a listing of proposed initiatives to improve research evidence
- Contains extensive citations to references, reviews, commentaries, and landmark studies
Evidence in Medicine is required reading for all researchers who create evidence, funders and publishers of medical research, students who conduct their own research studies, and healthcare practitioners wanting to deliver high-quality, evidence-based care.
Table of Contents
Preface 4
Aims of this book 5
Chapter 1 The rationale for treatment: a brief history 7
Conclusion 14
References 15
Chapter 2 Sources of bias in randomised controlled trials 18
Method of treatment allocation 18
Problems in measuring the outcome 20
Follow-up and missing outcomes 22
Missing outcome data and intention to treat 23
Other methodological concerns 24
Conclusions 26
References 27
Chapter 3 Wasted and unhelpful trials 34
Wasted Studies 34
Neglected areas of research 35
Unhelpful outcome measures 35
Lack of generalisability 37
Weak and misleading evidence 39
Conclusion 40
References 40
Chapter 4 Can the analysis bias the findings? 46
The p-value problem 46
Questionable research practices 48
Ensuring high quality analysis: the Statistical Analysis Plan 50
Conclusions 51
References 52
Chapter 5 Systematic reviews and Meta-analysis 56
Introduction 56
Identifying relevant trials 57
Extracting trial data 59
The quality of primary trials 61
Pooling effect sizes across trials 62
Other methodological issues 63
Conclusions 65
References 66
Chapter 6 Fabrication, falsification and spin 73
Fabrication 73
Falsification 75
Questionable Research Practices 76
Spin 76
Retractions 78
Discussion 78
References 79
Chapter 7 Why do researchers falsify data or manipulate study findings? 83
The research environment 83
Research oversight 86
Conflict of interest 88
Individual level explanations for research misconduct 90
How honest people rationalise misconduct 91
Discussion 93
References 94
Chapter 8 Developing a strategy to prevent poor quality and misleading research 103
Research environment 103
Research transparency 105
Research oversight 106
Research integrity 107
Essential elements of a transformational strategy 108
Implementing a programme for action 112
References 113
Appendix 1 Summary of the key findings on poor quality research 118
Problems in the design, conduct, analysis and reporting of studies 118
Frequency of data fabrication and falsification 120
The causes of poor quality and misleading research 120
The findings in perspective 121
References 122
Appendix 2 Initiatives to improve the quality of research 123
Change the research environment 123
Improve training 125
Increase research transparency 126
Quality of trial methodology 128
Trial registration 130
Reporting of the methods of systematic reviews 130
Increasing access to and use of reporting guidelines 132
Implement vigorous research oversight 132
Promote research integrity 136
Examples of coordinated initiatives 140
References 141
Index
