Evidence-Based Ophthalmology
2013; Elsevier BV; Volume: 120; Issue: 12 Linguagem: Inglês
10.1016/j.ophtha.2013.08.032
ISSN1549-4713
AutoresRichard Wormald, Kay Dickersin,
Tópico(s)Primary Care and Health Outcomes
ResumoIt is easy to assume that colleagues are familiar with the structure and function of the international Cochrane Collaboration (List of contributors to CEVG available at http://aaojournal.org), but often this is off the mark or their understanding is misinformed. The Collaboration consists of >30 000 persons around the world who are committed to responding to Archie Cochrane's challenge to the medical world in 1979:It is surely a great criticism of our profession that we have not organized a critical summary, by specialty or subspecialty, adapted periodically, of all relevant randomized controlled trials.1Cochrane A.L. 1931-1971: a critical review, with particular reference to the medical profession.in: Medicines for the year 2000. Office of Health Economics, London1979: 1-11Google Scholar His idea was that clinicians and patients should have access to the most up-to-date and reliable evidence about the effectiveness of healthcare interventions to inform their decisions. The rapid growth of the biomedical literature, which has not been paralleled by growth in quality, has meant that this task has become increasingly challenging. What do we do when we find several clinical trials, of equivalent quality, some of which show an intervention to be effective and some of which do not? Cochrane was Sir Iain Chalmers' mentor, the man who went on to develop the Oxford Database of Perinatal Trials. Because of the coincident emergence of methodologies of systematic reviewing and meta-analysis, Chalmers was able to take the challenge one step further by coauthoring Effective Care in Pregnancy and Childbirth. In 1987, the year before his death, Cochrane wrote the foreword to this book, referring to a systematic review of randomized, controlled trials (RCTs) of care during pregnancy and childbirth as “a real milestone in the history of randomized trials and in the evaluation of care.”2Cochrane A.L. Foreword.in: Chalmers I. Enkin M. Keirse M.J.N.C. Effective care inpregnancy and childbirth. Oxford University Press, Oxford1989Google Scholar He suggested that other specialties should copy the methods used. His encouragement, and the endorsement of his views by others, led to the opening of the first Cochrane Centre (in Oxford, UK) in 1992 and the founding of The Cochrane Collaboration in 1993.3The Cochrane Collaboration. Archie Cochrane: the name behind The Cochrane Collaboration. Available at: http://www.cochrane.org/about-us/history/archie-cochraneGoogle Scholar Discussions began immediately between Kay Dickersin and Iain Chalmers about the need for an Eyes and Vision Group (CEVG) within the collaboration, and the seed was sown for the group when later that year Iain Chalmers and Richard Wormald met at the Oxford Ophthalmological Congress. Two years later, an exploratory meeting was held in Montpelier (France) with eye care professionals largely from Europe and including Kay Dickersin, one of the cofounders of the Collaboration and Director of the US Cochrane Centre. Another key supporter and Collaboration cofounder was Alessandro Liberati, who with Luca Rossetti was an author of the first and highly influential systematic review in the ophthalmic literature on medical interventions for glaucoma4Rossetti L. Marchetti I. Orzalesi N. et al.Randomized clinical trials on medical treatment of glaucoma: are they appropriate to guide clinical practice?.Arch Ophthalmol. 1993; 111: 96Crossref PubMed Scopus (80) Google Scholar—a much-needed alarm to the specialty to get to establish appropriate evidence in support of practice standards. The CEVG was officially registered in 1997 with its editorial base at the Institute of Ophthalmology in London with funding from the National Institute for Health Research (the UK's equivalent to the US National Institutes of Health). And in 2002, the National Eye Institute, part of the National Institutes of Health, funded a CEVG Satellite, currently based at The Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland ([email protected]). Now, after 15 years of systematic reviewing, we can look back at what has been achieved and look forward to new challenges. We can boast >100 systematic reviews on the Cochrane Database of Systematic Reviews, of which at least half of which have recently been updated. However, many are “empty”—one quarter of reviews on important questions about common interventions contain no trials of sufficient quality or with the relevant outcomes to give an answer, and many more are inconclusive. This is often a source of frustration to those who access the Cochrane database and leads to an expectation that we should include studies of lesser quality or studies using nonrandomized designs. What to do when there are no acceptable RCTs is the subject of continuing debate within the Collaboration, but for questions about effectiveness of healthcare interventions, most would agree that RCTs are the only acceptable design for control of bias and confounding. Systematically reviewing unsound evidence simply amplifies error. However, if no RCTs on the topic were identified for the systematic review, we do encourage our authors to describe the nature of the existing evidence base for an intervention in the discussion section. This approach recognizes that the studies mentioned were selected by the authors for comment and were not systematically searched for, evaluated, or subjected to meta-analysis. Ultimately, our patients should be justified in expecting that decisions about therapeutic interventions are based on the highest quality evidence. This year, the Collaboration is 20 years old and across all the entities extra efforts are being made to make people aware of the Collaboration's achievements. These include the 52 review groups (of which CEVG is just one), national centers (of which the US Cochrane Center at Johns Hopkins Bloomberg School of Public Health is 1 of 13), center branches, and other methods and advocacy groups. What have we learned through CEVG's systematic reviews? Here are a few highlights:•Patching is wrong for corneal abrasions.5Turner A. Rabiu M. Patching for corneal abrasion.Cochrane Database Syst Rev. 2006; : CD004764PubMed Google Scholar•Screening the elderly for sight loss does not reduce the prevalence of vision impairment, at least in the existing models.6Smeeth L.L. Iliffe S. Community screening for visual impairment in the elderly.Cochrane Database Syst Rev. 2006; : CD001054PubMed Google Scholar•Vitamin supplements for the prevention of cataract make no difference (although the recently published findings of Age-Related Eye Disease Study [AREDS] 2 are yet to be included7Mathew M.C. Ervin A.M. Tao J. Davis R.M. Antioxidant vitamin supplementation for preventing and slowing the progression of age-related cataract.Cochrane Database Syst Rev. 2012; : CD004567PubMed Google Scholar).•Vitamin E and β-carotene do not prevent age-related macular degeneration.8Evans J.R. Lawrenson J.G. Antioxidant vitamin and mineral supplements for preventing age-related macular degeneration.Cochrane Database Syst Rev. 2012; : CD000253PubMed Google Scholar•Nonsteroidal anti-inflammatory agents (probably) are effective in treating macula edema after cataract surgery.9Sivaprasad S. Bunce C. Crosby-Nwaobi R. Non-steroidal anti-inflammatory agents for treating cystoid macular oedema following cataract surgery.Cochrane Database Syst Rev. 2012; : CD004239PubMed Google Scholar•Antimetabolites decrease the risk of failure of trabeculectomy.10Clarke J.C.K. Schlottmann P.G. Mitomycin C versus 5-fluorouracil for wound healing in glaucoma surgery (Protocol).Cochrane Database Syst Rev. 2006; : CD006259Google Scholar•Acyclovir is marginally better than trifluorothymidine at accelerating the healing of a herpetic dendritic ulcer.11Wilhelmus K.R. Antiviral treatment and other therapeutic interventions for herpes simplex virus epithelial keratitis.Cochrane Database Syst Rev. 2010; : CD002898PubMed Google Scholar Other reviews identify uncertainty and have led to new trials. Lens extraction for angle closure glaucoma12Friedman D. Vedula S.S. Lens extraction for chronic angle-closure glaucoma.Cochrane Database Syst Rev. 2006; : CD005555PubMed Google Scholar and selective laser trabeculoplasty for open-angle glaucoma are examples.13Rolim de Moura C.R. Paranhos Jr., A. Wormald R. Laser trabeculoplasty for open angle glaucoma.Cochrane Database Syst Rev. 2007; : CD003919PubMed Google Scholar Another important role of the Collaboration is to develop methodologies to improve the reliability of systematic reviews and extend their relevance to users. Over the last few years, all new and updated reviews include “Risk of Bias” tables, which enable the reader to see at a glance the quality of evidence available to answer the question the review addresses. Five aspects of design, conduct, and reporting characteristics (randomization, allocation concealment, masking, attrition postrandomization, and selective outcome reporting) are graded to alert the reader to areas of possible concern. A simple traffic light code—red for high risk of bias, yellow for uncertain, and green for low—is provided for all included trials and sometimes for specific outcomes within trials. Understanding the weight of all the evidence assembled, once the individual studies have been assessed for risk of bias, is essential for interpreting the findings of a review and for informing those who write clinical practice guidelines. This is the function of the Summary of Findings table using Grade Pro software,14Brozek J, Oxman A, Schünemann H. GRADEpro [Computer program]. Version 3.2 for Windows. 2008.Google Scholar which has been introduced for new and more complex reviews. A significant effect may emerge from a meta-analysis, but if the weight of the evidence (i.e., all trial findings taken together) is uncertain or at high risk of bias, or if one trial of uncertain quality is dominating the findings, the overall results must be interpreted with caution The CEVG uses guidelines to identify gaps in the evidence and topics where systematic reviews and trials are needed. Specifically, [email protected] has used the American Academy of Ophthalmology's Preferred Practice Patterns for open-angle and angle-closure glaucoma to identify questions not yet answered by systematic reviews or RCTs.15Li T. Ervin A.-M. Scherer R. et al.Setting priorities for comparative effectiveness research: a case study using primary open-angle glaucoma.Ophthalmology. 2010; 117: 1937-1945Abstract Full Text Full Text PDF PubMed Scopus (22) Google Scholar, 16Li T. Vedula S.S. Scherer R. Dickersin K. What comparative effectiveness research is needed? A framework for using guidelines and systematic reviews to identify evidence gaps and research priorities.Ann Intern Med. 2012; 156: 367-377Crossref PubMed Scopus (52) Google Scholar, 17Yu T. Li T. Lee K.J. et al.Setting priorities for comparative effectiveness research on management of primary angle closure: a survey of Asia-Pacific Clinicians.J Glaucoma. 2013 Jul 3; ([Epub ahead of print])Google Scholar This work also helps us to prioritize our reviews according to what ophthalmologists tell us is important. And in addition to those in glaucoma already mentioned, we have ongoing projects in age-related macular degeneration, dry eye, diabetic retinopathy, and cataract. In this way and others, guideline writers are helped by CEVG. One of the toughest areas for getting a reliable answer is knowing which of several available treatment options work best. To achieve this goal, network meta-analyses are needed18Li T. Puhan M. Vedula S.S. et al.Network meta-analysis: highly attractive but more methodological research is needed.BMC Medicine. 2011; 9: 79Crossref PubMed Scopus (245) Google Scholar and researchers at [email protected], including Tianjing Li, who serves on the editorial board of Ophthalmology, are working on this. With funding from the National Eye Institute, Dr Li is using this new methodology to see what works best using data from hundreds of trials identified on the management of open-angle glaucoma. Studies about the accuracy of diagnostic testing are of obvious importance in ophthalmology, and new methodologies of the Collaboration have taken on their systematic review. Gianni Virgili leads this initiative for CEVG from a new editorial base at the University of Florence. One review is published19Virgili G. Menchini F. Murro V. et al.Optical coherence tomography (OCT) for detection of macular oedema in patients with diabetic retinopathy.Cochrane Database Syst Rev. 2011; : CD008081PubMed Google Scholar and another is in progress. The prodigious productivity of CEVG is possible because of the >800 eye care professionals and others who contribute as review authors. Not only do authors take on the often underappreciated task of synthesizing data from multiple disparate trials, they also keep them up to date, a sometimes even larger task. Indeed, online publication of evidence through The Cochrane Library offers the opportunity to keep evidence up to date, something that cannot be achieved by textbooks. As the portfolio of CEVG reviews steadily grows, the challenge of keeping them current becomes increasingly hard to manage and we have had to develop strategies for prioritization. But relying on outdated reviews is potentially dangerous, as is relying on improperly conducted reviews. We are committed to finding the resources needed to meet this challenge. To become an author for CEVG, visit our website (http://eyes.cochrane.org/), become familiar with our reviews (www.thecochranelibrary.com), and work with us to find a topic in your interest area. We have training workshops in the United States twice a year, and other training opportunities are available worldwide. Because of the National Eye Institute support for CEVG-US, US authors have a strong support system of methodologists for their reviews. The CEVG also offers other educational opportunities, via our website, including online courses on evidence-based healthcare and how to be an effective peer reviewer. Editors Augusto Azuara-Blanco, PhD, FRCS(Ed), FRCOphth Jennifer Burr, MRCOphth, DO, MSc, MBChB Kay Dickersin, PhD, MA Marie Diener-West, PhD Sue Elliott, BSc(Hons), MSc Jennifer Evans, BA (Cantab), MSc, PhD Daniel Ezra, MD, MRCOphth Scott Fraser, MB, ChB, FRCS(Ed), FRCOphth MD David Friedman, MD, PhD, MPH Stephen Gichuhi, MBChB, MMed, MSc, MBA Sarah Hatt, DBO Barbara Hawkins, PhD Tianjing Li MD PhD MHS Jod Mehta, BSc(Hons.), MBBS, FRCOphth, FRCS(Ed) Roberta Scherer, PhD Alex Shortt, MSc, MRCOphth Gianni Virgili, MD Stephanie Watson, BSc(Med), MBBS, PhD, FRANZCO Kirk Wilhelmus, MD, MPH, PhD David Yorston, FRCS, FRCOphth Editorial Team Anupa Shah – Managing editor UK Iris Gordon – Trial Search coordinator UK Ann Ervin, MPH, PhD - Project Director, [email protected] Lisa Lassiter - Assistant Managing Editor US Lori Rosman -Trials Search Coordinator US Claire Twose- Trials Search Coordinator US Kristina Lindsley, MHS - Methodologist US Michael Marrone, MPH – Methodologist US Ian Saldanha, MBBS, MPH - Methodologist US Xue Wang, MBBS, MSPH – Methodologist US Sandy Forman, MS - Consultant Methodologist US Nancy Fitton, MHS - Consumer Coordinator US
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