What is evidence-based ophthalmology? Introducing the Cochrane Eyes and Vision Group
An evidence-based approach to health care delivery is not new. Research has informed clinical practice for centuries, but within the last decade a growing body of enthusiasts are advocating a more structured approach to the use of evidence in practice. There are many influences on our work; most important perhaps is what and how we were taught. The traditional approach of medical training is to learn and memorise lists of facts. The modern approach is to teach doctors how to ask questions and challenge established values. What is the evidence that one treatment is better than another? How precise is a test in separating people affected by a condition from those who are not?
In answering these questions, it is no longer sufficient to resort to the well thumbed text book; today, it is likely to be out of date and often the evidence underlying the authority of the text is not given. The growth of research and the publication of its findings in medical literature are so rapid that it becomes impossible for any clinician to keep abreast of the latest developments. It is especially challenging for people working in areas where access to well stocked libraries can be difficult, if not impossible.
Those involved with evidence-based medicine are committed to breaking down the old structures of knowledge where the best wisdom was stored in inaccessible centres of excellence, and to ensuring that all practitioners, however remote or distant they are from centres of learning, have access to it.
Where health care resources are scarce, it is especially important that limited funds are used on interventions and services based on sound evidence. Furthermore, poorer countries may be exposed to influences which do more harm than good: exploitation by richer economies is not unusual; pharmaceutical companies may have greater freedom to behave less than ethically where they find themselves without competition – inflating prices or trading obsolete or harmful remedies rejected elsewhere. Sometimes the zeal ‘to do good’ in poorer countries misfires when enthusiasm overlooks the lack of evidence of benefit or indeed the possibility that an intervention may be harmful. Such was the case for diethylcarbamazine in the treatment of River Blindness, which caused, rather than prevented, blindness.
The International Cochrane Collaboration is a network of individuals in all specialities of medicine dedicated to preparing, maintaining and promoting access to systematic reviews of the best evidence of the benefits and risks of health care interventions. Cochrane systematic reviews are intended to help people (health professionals, policy makers and consumers) make practical decisions. The Cochrane Eyes and Vision Group (CEVG) exists to do this for eye care internationally and is committed to support the efforts of VISION 2020 by providing the evidence-base for practice and policies to eliminate avoidable blindness.
Beginning with this short introduction, we propose to launch a series on evidence-based ophthalmology starting with the basics and continuing to promote an understanding of its relevance to eye care. The next issue will include an article about the nature of evidence and evidence hierarchies with more on what evidence-based medicine actually involves. The CEVG is delighted that Community Eye Health will provide a means for disseminating the findings of its reviews and hopes that it will become a means of recruiting contributors from its readership.