Menu Expand
BMJ Research Methods and Reporting: General topics & statistics volume 2

BMJ Research Methods and Reporting: General topics & statistics volume 2

Professor Adrian Hunnisett

(2016)

Additional Information

Book Details

Abstract

The routine use of patient reported outcome measures in healthcare settings Strengths and weaknesses of hospital standardised mortality ratios Importance of accurately identifying disease in studies using electronic health records Verification problems in diagnostic accuracy studies: consequences and solutions Interpretation of random effects meta-analyses Differential dropout and bias in randomised controlled trials: when it matters and when it may not Rethinking pragmatic randomised controlled trials: introducing the "cohort multiple randomised controlled trial" design Correlation in restricted ranges of data Is a subgroup effect believable? Updating criteria to evaluate the credibility of subgroup analyses Target practice: choosing target conditions for test accuracy studies that are relevant to clinical practice Use of serial qualitative interviews to understand patients' evolving experiences and needs Use of multiperspective qualitative interviews to understand patients' and carers' beliefs, experiences, and needs Meta-analysis of individual participant data: rationale, conduct, and reporting An IV for the RCT: using instrumental variables to adjust for treatment contamination in randomised controlled trials Random measurement error and regression dilution bias The double jeopardy of clustered measurement and cluster randomisation Implementation research: what it is and how to do it A multicomponent decision tool for prioritising the updating of systematic reviews The impact of outcome reporting bias in randomised controlled trials on a cohort of systematic reviews Assessing equity in systematic reviews: realising the recommendations of the Commission on Social Determinants of Health Prognosis and prognostic research: what, why, and how? Prognosis and prognostic research: Developing a prognostic model Prognosis and prognostic research: validating a prognostic model Prognosis and prognostic research: application and impact of prognostic models in clinical practice Ten steps towards improving prognosis research Prognosis research strategy (PROGRESS) 1: A framework for researching clinical outcomes Prognosis Research Strategy (PROGRESS) 2: Prognostic factor research Prognosis Research Strategy (PROGRESS) 3: Prognostic model research Prognosis research strategy (PROGRESS) 4: Stratified medicine research

Table of Contents

Section Title Page Action Price
Book Cover C
Title i
Copyright ii
About the publisher iii
About The BMJ iii
Contents iv
About the editors vi
Introduction to Research Methods and Reporting series vii
The routine use of patient reported outcome measures in healthcare settings 1
Using an appropriate validated measure 1
Data collection and storage 2
Minimising missing and duplicated data 3
Thinking about data analysis 3
Conclusions 3
Strengths and weaknesses of hospital standardised mortality ratios 5
What is an HSMR? 5
How they are used 5
Methodological uncertainties 5
Numerator 5
Denominator 5
Risk modelling 7
Interpretation 7
Coding 8
Importance of accurately identifying disease in studies using electronic health records 9
How disease classification errors affect study conclusions 9
Estimating bias 9
Why does this problem happen? 11
Assessment of bias 11
Conclusion 12
Verification problems in diagnostic accuracy studies: consequences and solutions 14
Partial verification 14
Clinical examples of partial verification 14
Potential for bias 14
Corrections for partial verification bias 15
Differential verification 15
Clinical example 16
Further corrections for differential verification bias 17
Conclusion 17
Interpretation of random effects meta-analyses 19
Difference between fixed effect and random effects meta-analyses 19
Fixed effect meta-analysis 19
Random effects meta-analysis 19
Use and interpretation of meta-analysis in practice 20
Benefits of using prediction intervals 20
Examples 21
Antidepressants for reducing pain in fibromyalgia syndrome 21
Inpatient rehabilitation in geriatric patients 21
Discussion 21
Differential dropout and bias in randomised controlled trials: when it matters and when it may not 23
Introduction 23
Example 23
Key concepts 23
Types of missing data 23
Statistical analysis: what works and what does not work 24
Simulation study 25
Discussion 26
Rethinking pragmatic randomised controlled trials: introducing the “cohort multiple randomised controlled trial” design 28
Introduction 28
Problems with randomised controlled trials 28
Recruitment 28
Ethics 28
Patient preferences 28
Treatment comparisons 28
Previous solutions 29
The “cohort multiple randomised controlled trial” design 29
Randomisation: random selection of some 29
Information and consent: “patient centred” 30
Benefits of the approach 30
Role of the cmRCT design 30
Challenges of the design 30
Examples of the cmRCT design 31
Summary 31
Correlation in restricted ranges of data 33
Is a subgroup effect believable? Updating criteria to evaluate the credibility of subgroup analyses 34
Introduction 34
Relative versus absolute effect in subgroup analyses 34
The original seven criteria for subgroup analyses 35
New criteria to judge the credibility of subgroup effects 35
1 Is the subgroup variable a characteristic measured at baseline or after randomisation? 35
2 Was the direction of the subgroup effect specified a priori? 35
3 Is the significant subgroup effect independent? 35
4 Is the interaction consistent across closely related outcomes within the study? 36
Discussion 37
Target practice: choosing target conditions for test accuracy studies that are relevant to clinical practice 39
Defining disease for test accuracy studies 39
The target condition 39
Why target condition should be clinically defined 40
Clinical implications 41
Research implications 41
Use of serial qualitative interviews to understand patients’ evolving experiences and needs 43
When to use serial interviews 43
How do you conduct serial interview studies? 43
Recruitment 43
Data generation 43
Analysis 44
What type of findings might you expect? 44
Issues that change over time 44
Rich and contextualised accounts 45
Pitfalls and how to avoid them 45
Ethical issues 45
Attrition 45
Data overload 45
Conclusions 45
Use of multiperspective qualitative interviews to understand patients’ and carers’ beliefs, experiences, and needs 47
When are multiperspective interviews appropriate? 47
How do you conduct multiperspective interview studies? 47
Recruitment 47
Data generation 47
Analysis 48
What type of findings might you expect? 48
Understanding of relationships and dynamics 48
Comparison of perceptions of patients, their family, and carers 48
Understanding of individual needs of participants 49
Suggestions for improving services 49
Potential pitfalls and how to avoid them 49
Recruitment issues 49
Patients and carers opting to be interviewed together 49
Ethical issues 49
Lack of clarity about aims and analytical strategy 49
Conclusions 49
Meta-analysis of individual participant data: rationale, conduct, and reporting 51
What are individual participant data? 51
What is an individual participant data meta-analysis? 51
Incidence of individual participant data meta-analyses over time 52
When do an aggregate data meta-analysis and an individual participant data meta-analysis coincide? 52
What are the advantages of a meta-analysis of individual participant data? 53
Differences in conclusions with regard to a treatment effect 53
Example 1: Effectiveness of laparoscopic repair at reducing persistent pain 53
Example 2: Effectiveness of paternal white blood cell immunisation at reducing recurrent miscarriage 53
Differences in conclusions with regard to how patient level characteristics modify treatment effect 53
Example 1: Effect of elevated panel reactive antibodies on the effectiveness of antilymphocyte antibody induction 53
Example 2: Effect of gender on the effectiveness of hypertension treatment 54
Beyond the “grand mean” 54
What are the disadvantages of a meta-analysis of individual participant data? 54
How to obtain individual participant data for a meta-analysis 55
Reporting individual participant data meta-analyses 55
An applied example of an individual participant data meta-analysis of hypertension trials 55
Conclusions 56
An IV for the RCT: using instrumental variables to adjust for treatment contamination in randomised controlled trials 58
Introduction 58
Background: What do we do now, and what’s wrong with it? 58
Using instrumental variables to help us understand results of randomised controlled trials 59
Real world examples 60
What are the benefits and limitations of CA ITT estimates? 60
Advanced IV analysis 61
Conclusion 61
Random measurement error and regression dilution bias 63
Introduction 63
Example 63
Random measurement error in the exposure (X) variable 63
Measurement error in the outcome (Y) variable 64
Why does the slope not flatten in this situation? 64
Recommendations for researchers 65
The double jeopardy of clustered measurement and cluster randomisation 67
Clustered measurement 67
Combined clustering: “double jeopardy” 67
Recent example 68
What can be done to minimise double clustering? 69
Conclusion 69
Implementation research: what it is and how to do it 70
Defining implementation research 70
Principles of implementation research 70
Implementation outcome variables 71
Implementation strategies 71
Implementation influencing variables 71
Implementation research questions 71
Implementation specific research methods 72
Pragmatic trials 73
Effectiveness-implementation hybrid trials 73
Quality improvement studies 73
Participatory action research 74
Mixed methods 74
Conclusion 74
A multicomponent decision tool for prioritising the updating of systematic reviews 76
Development and evaluation of the qualitative decision tree 76
Development and evaluation of the quantitative tool 76
Development and evaluation of the multicomponent updating decision tool 76
Overview of the multicomponent updating decision tool 77
Documentation and presentation of decisions 77
Discussion 77
The impact of outcome reporting bias in randomised controlled trials on a cohort of systematic reviews 81
Methods 82
Assessment of systematic reviews 82
Classification of randomised controlled trials in systematic reviews 82
Accuracy of classification 83
Amount and impact of missing trial data 83
Results 84
Assessments of systematic reviews 84
Full reporting of review primary outcomes in trials 84
Classification of trials 84
Accuracy of classification 84
Amount and impact of missing trial data 85
Discussion 86
Strengths and limitations of the study 86
Comparison with other studies 87
Implications for systematic reviews 87
Future research 89
Assessing equity in systematic reviews: realising the recommendations of the Commission on Social Determinants of Health 91
Background to health inequalities and inequities 91
The need for adequate reporting of health equity effects 91
Process of developing recommendations 91
Challenges and recommendations 92
1. Developing a logic model 92
2. Defining disadvantage and for whom interventions are intended 92
3. Deciding on the appropriate study design(s) 92
4. Identifying the appropriate outcomes 92
5. Process evaluation and understanding context 93
6. Data analysis and presentation 93
7. Applicability of findings 94
Conclusions 94
Prognosis and prognostic research: what, why, and how? 96
What is prognosis? 96
Multivariable research 96
Use of prognostic models 96
Differences from aetiological research 97
How to study prognosis? 97
Objective 97
Study sample 97
Study design 97
Predictors 97
Outcome 98
Required number of patients 98
Validation and application of prognostic models 98
Prognosis and prognostic research: Developing a prognostic model 100
Preliminaries 100
Selecting candidate predictors 100
Evaluating data quality 100
Data handling decisions 100
Selecting variables 101
Modelling continuous predictors 101
Assessing performance 101
Example of prognostic model for survival with kidney cancer 101
Discussion 102
Prognosis and prognostic research: validating a prognostic model 105
Why prognostic models may not predict well 105
Design of a validation study 105
Comparing predictions with observations 105
Case studies 106
Predicting operative mortality of patients having cardiac surgery 106
Predicting postoperative mortality after colorectal surgery 106
Predicting failure of non-invasive positive pressure ventilation 106
Predicting complications of acute cough in preschool children 106
Discussion 107
Prognosis and prognostic research: application and impact of prognostic models in clinical practice 109
Limitations to application 109
Extrapolation versus validation 109
Adequate prediction versus application 109
Usability 110
Changes over time 110
Evidence beyond validation studies 110
Adjusting and updating prognostic models to improve performance 110
Impact of prognostic models 110
When to apply a prognostic model? 111
Concluding remarks 111
Ten steps towards improving prognosis research 113
Problems with prognosis research 113
Purpose 113
Funding 114
Protocols 114
Predictors 115
Outcomes 115
Methods 115
Publication 115
Reporting 115
Synthesis 115
Impact of research 116
Conclusion 116
Prognosis research strategy (PROGRESS) 1: A framework for researching clinical outcomes 118
What is fundamental prognosis research? 120
Importance of fundamental prognosis research in the pathways toward improved health outcomes 120
Importance for public health policy 120
Importance for comparative effectiveness and health services research 121
Importance for health technology assessment of imaging and other tests 121
Importance for trials and decision models 121
Importance for new approaches, mechanisms, and targets for trials 121
Importance for overcoming the limitations of diagnosis 122
Importance for discovering new diseases 122
Recommendations for improving the quality and impact of prognosis research 123
Fuelling changes in medicine and healthcare 123
Electronic health records 123
Visibility of the field 124
Teaching and training 124
Patient and public involvement 124
Conclusion 124
Prognosis research strategy (PROGRESS) 4: Stratified medicine research 127
What is stratified medicine? 127
Why is prognosis research important for stratified medicine? 128
Assessing priorities for stratified medicine 129
Evaluation in randomised trials 129
Assessment of tests as a health technology 129
Cost effectiveness evaluations 130
Healthcare policy and delivery 130
Recommendations for improving prognosis research for stratified medicine 130
False negative findings (type II errors) 130
False positive findings (type I errors) 130
Analyses restricted to just individuals testing positive for a factor, or just individuals receiving treatment 131
Biological reasoning and prioritisation of funding areas 131
Conclusions 132
More titles in The BMJ Series 134
More titles in The BMJ Research Methods and Reporting Series 135
More titles in The BMJ Research Methods and Reporting Series 136
More titles in The BMJ Easily Missed? Series 137
More titles in The BMJ Easily Missed? Series 138
More titles in The BMJ Clinical Review Series 139
More titles from BPP School of Health 140
More titles in The Progressing Your Medical Career Series 141
More titles in The Progressing Your Medical Career Series 142
More titles in The Progressing Your Medical Career Series 143
More titles in The Essential Clinical Handbook Series 144
More titles in The Essential Clinical Handbook Series 145