Systematic Reviews to Support Evidence-Based Medicine: How to appraise, conduct and publish reviews

239 Pages·2022·7.278 MB·English

by  Khalid S. Khan, Javier Zamora

Systematic
Reviews
TO SUPPORT EVIDENCE-
BASED MEDICINE
Authoritative, clear and concise, this award-winning book continues to be an essential text for
all medical, surgical and allied health professionals who are seeking a quick and respected guide
to systematically reviewing the literature. The third edition features a new chapter on ‘Publishing
systematic reviews’ and numerous new case studies covering the latest developments in the field,
including umbrella reviews, reviews of test accuracy, qualitative evidence, prognostic studies, and
practice guidelines.
The highly experienced authors, who have each contributed to numerous systematic reviews
that have helped form policy and practice, ensure that this practical text, which avoids technical
jargon, continues to be the reference of choice for all health professionals undertaking literature
reviews, including those specializing in epidemiology and public health.

Systematic
Reviews
TO SUPPORT EVIDENCE-
BASED MEDICINE
HOW TO APPRAISE, CONDUCT
AND PUBLISH REVIEWS
THIRD EDITION
Khalid S. Khan
Beatriz Galindo Distinguished Investigator and Professor
of Preventive Medicine and Public Health at the
University of Granada, Spain
Researcher of the Spanish Research Network in
Epidemiology and Public Health (CIBERESP)
Javier Zamora
Head of the Clinical Biostatistics Unit at Ramon y Cajal
University Hospital (IRYCIS), Madrid, Spain
Professor of Biostatistics in Maternal and Perinatal Health
at the University of Birmingham, UK
Researcher of the Spanish Research Network in
Epidemiology and Public Health (CIBERESP)
Third edition published 2023
by CRC Press
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and by CRC Press
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CRC Press is an imprint of Taylor & Francis Group, LLC
Second edition published 2011
© 2023 Khalid S. Khan and Javier Zamora
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ISBN: 9781032114736 (hbk)
ISBN: 9781032114675 (pbk)
ISBN: 9781003220039 (ebk)
DOI: 10.1201/9781003220039
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Contents
Preface vii
About the authors ix
Acknowledgements xi
Additional contributors xiii
Abbreviations xv
Introduction xvii
Steps of a systematic review
Step 1: Framing questions for a review 3
Step 2: Identifying relevant literature 21
Step 3: Assessing the quality of the literature 37
Step 4: Summarizing the evidence 53
Step 5: Interpreting the findings 75
Case studies
Case study 1: Review of systematic reviews 93
Case study 2: Reviewing the safety of a public health intervention 99
Case study 3: Reviewing the effectiveness of therapy 109
Case study 4: Reviewing the accuracy of a test 121
Case study 5: Reviewing qualitative evidence to evaluate patient
experience 133
Case study 6: Reviewing the effects of educational interventions 143
Case study 7: To use or not to use a therapy? Incorporating evidence
on harmful outcomes 153
Case study 8: Review of clinical practice guidelines 165
Case study 9: Systematic reviews to assess a prognostic factor 171
Case study 10: Publishing systematic reviews: Tips and tricks for
convincing journal editors and peer reviewers 181
Glossary 193
Suggested reading 207
Index 209
v

Preface
Are you about to start working on your first review project? Do you wish to become a published
author of a systematic review? Are you embarking on a career in public health, epidemiology or
health technology assessment? Are you a clinical teacher interested in discovering the likely edu-
cational effects of the courses you deliver? Are you interested in health from the social science
perspective? Are you a health professional who wishes to improve the quality of your practice
using guidelines? If so, this book is for you.
The first two editions of this book exceeded all expectations. It was commended in the Basis
of Medicine category in the BMA Medical Book competition 2003. Commentators found it a
clear, useful guide to a potentially off-putting topic that built the confidence of non-statisticians.
The British Journal of Surgery called it a ‘gem’. It recognized that this book stood head and
shoulders above other texts on account of its brevity and clarity of prose. It advised readers
that if they ever read or wrote systematic reviews, they should read this book first. It was praised
for conveying an enthusiasm that made the reader want to conduct a review of their own. Its
well-organized materials, logical structured flow, useful worked examples and case studies led to
it being recommended to libraries of educational and research institutions concerned with health
sciences. It was directed at novice reviewers, and it has been cited hundreds of times, indicating
that even seasoned researchers have taken an interest in its contents. With the passage of time,
a third edition became imperative. Like its predecessors, this edition describes the main principles
behind systematic reviews of healthcare research and provides guidance on how reviews can be
appraised, conducted and applied in practice. It adds guidance on how to write up reviews for
publication in peer-reviewed journals.
As our healthcare practice and policy increasingly relies on clear and comprehensive summaries
of information collated through systematic literature reviews, it is necessary for us to under-
stand how reviews and clinical practice guidelines are produced. You may not be trained in health
research methods, but this book will enable you to grasp the principles behind reviewing published
literature. In this way, you will be able to critically appraise published systematic reviews and
guidelines, and evaluate their inferences and recommendations for application in your practice.
Published reviews and guidelines are not always adequate or sufficient for our needs. Have you
ever wondered how you could conduct your own review? The resources required for undertaking
reviews are available in a clinical setting. The appointment of clinical librarians, internet access
to journals, ease of obtaining papers online and the availability of user-friendly software make
it possible for systematic reviews to be conducted by healthcare practitioners and bachelor’s
or master’s degree students. This book highlights the core information necessary for planning,
preparing and publishing reviews. It focuses on a clinical readership and new reviewers, not on
experienced epidemiologists and statisticians. Using this book, you will be able to initiate your
own review and write it up for publication in a peer-reviewed journal.
What is new in this edition of the book? We have widened the scope to go beyond the eval-
uation of the effectiveness of interventions in healthcare. We demonstrate how reviews can be
usefully applied to evaluate qualitative and educational research. We have thoroughly overhauled
the section and examples on how to interpret the findings of a review, leading to judicious and
credible recommendations for clinical practice. We have added a substantial number of new case
studies, providing more worked illustrations of key concepts.
What is totally new in this book is its additional content on how to write up the manuscript of
a review for publication. New reviewers just don’t have the confidence to go ahead with writing
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viii Systematic Reviews to Support Evidence-Based Medicine
up their reviews. A master’s degree student may have undertaken a literature review for preparing
their thesis. Their effort is visible in the detailed manuscript, but it is far too wordy for a published
article. How can the written work be cut down in size from 50,000 to 3,000 words? This book will
take new reviewers through the manuscript writing process so that they can confidently submit a
quality manuscript compliant with all reporting guidelines and journals’ instructions.
For too many years there has been a mystery surrounding systematic reviews and reviewers.
How did they select certain studies and reject others? What did they do to collate the results? How
did a bunch of insignificant findings suddenly become significant? How did they capture a very
large body of evidence summarized in a succinct published article? You are about to embark on a
journey that will demystify these intrigues. Enjoy reading and get your review published.
Khalid S. Khan
Javier Zamora
About the authors
Together we are veterans of over 300 published systematic reviews. Over the years we have worked
with healthcare commissioners, clinicians and other decision-makers, producing reviews to inform
policy and practice. We have collaborated with other epidemiologists and statisticians to advance
methods for undertaking systematic reviews. The two of us work in a clinical academic setting
producing, promoting and applying systematic reviews to inform practice. We have supervised
many students to undertake graduate and doctoral thesis work based on systematic reviews and
to publish their reviews in peer-reviewed journals.
Khalid S. Khan is Professor and Distinguished Investigator in Public Health and Preventive
Medicine at the University of Granada, Spain. He has been Professor at the University of
Birmingham and the Queen Mary University of London, UK, and Spinoza Professor at the University
of Amsterdam, the Netherlands. With an h-index >100, he has published over 150 peer-reviewed
systematic review papers collating data from 6415 studies with 68,798,079 participants. He is
among the top 2% most influential scientists in the world. He is a clinician, trained in systematic
reviews and evidence-based medicine (EBM). Qualified in medical education, he has run journal
clubs and other EBM activities, including evidence-supported ward rounds and workshops on crit-
ical appraisal. He teaches undergraduates and postgraduates. His Core Outcomes in Women’s and
Newborn Health (CROWN) initiative was awarded a BMA Strutt and Harper grant to help reduce
research waste. He is former Editor of BJOG, EBM-BMJ and BMC Med Educ. In this role, over
10,000 manuscripts have been evaluated for publication under his editorship. He runs an active
teaching programme for researchers and reviewers on how to write up manuscripts that editors
find acceptable for publication.
Javier Zamora is Professor of Biostatistics at the University of Birmingham, UK, and Head of
the Clinical Biostatistics Unit of the Ramon y Cajal Hospital (IRYCIS Research Institute) in Madrid,
Spain. He has been Senior Lecturer at the Queen Mary University of London, UK, and Associate
Professor at the Complutense University of Madrid, Spain. He is also among the top 2% most
influential scientists in the world. He leads a research group of Epidemiology and Public Health
within the CIBERESP research excellence network in Spain. He is also Deputy Head of the Madrid
Associate Cochrane Centre where he supports the production and dissemination of evidence syn-
thesis activities. He has been involved as a statistician and methodologist in many systematic
reviews and meta-analyses which have been published in high-ranking journals such as Cochrane
Database of Systematic Reviews, JAMA, Annals of Internal Medicine, Lancet, BMJ and PLoS
Medicine. He has been the statistical editor of BJOG and has acted as a statistical referee of many
peer-reviewed journals. His teaching activities focus on methodology for clinical primary research
and for producing evidence syntheses to promote EBM.
We have put this book together because we feel that healthcare professionals have much to gain
from reviews and guidelines and, at the same time, reviews and guidelines have much to gain
from them. With this book, we hope healthcare practitioners will feel empowered to use reviews
effectively, to initiate their own reviews to collate the published literature systematically and to
publish their reviews confidently in peer-reviewed journals.
ix