![]() The ‘Bright Eyes’ story is not an isolated instance and the internet is full of claims for various lotions and potions, elixirs and miracle cures many supported by ‘research evidence’ and by grand sounding experts (you can even buy yourself a PhD from an internet-based ‘University’ if you think you deserve one). The next step down from RCTs are controlled observational studies, including cohort and case control studies, with prospective studies typically providing stronger evidence than retrospective studies. 8 However, the placebo effect can be substantial and in a later placebo-controlled anti-cataract drug trial, the placebo group showed what could be argued to be at least 21% and up to 81% effective after 1 year (21% improvement in visual acuity by two lines, 60% no change). 73% effective, with 39% improvement in visual acuity and 34% no change). Some drugs were reported to show effectiveness in a very high percentage of cases (e.g. 7 Prior to double blind, randomised, placebo controlled trails, cataract drugs were assessed in open trials and cataract drugs were claimed to be effective if vision improved or stayed the same over a period of time. In addition, the research report concentrated on improvements with the eyedrops, with less emphasis on the much more important comparisons with the (inadequate) control group. only about a half of the control group were given a placebo. The claims were based on an open study of three patients on the TV show and by vastly over-exaggerating the results from one small, poorly designed trial from the research literature in which the control group included 13 patients using a placebo and 10 who did not receive eyedrops. This included the statement that ‘doubling the dose – without any harm – some patients have eradicated their cataracts in <7 weeks’ amongst others. Please note that links to all cited websites are provided in the online version of this editorial.Ī high profile example of the importance of understanding RCTs and other research evidence were the claims made for ‘Bright Eyes’ eyedrops that ‘dissolve cataracts naturally’ in the Daily Mail and the Richard & Judy TV show. These two subjects are the topic of an invited review by Alicja Rudnicka and Christopher Owen in an upcoming issue of OPO. ![]() 6 The gold standard for research evidence are randomized controlled trials (RCTs) that are double-blind and placebo controlled and the highest possible level of evidence is an aggregation of the evidence from several RCTs using a systematic review and/or meta-analysis. In addition, research evidence has a hierarchy of robustness. It requires the selection of tests and treatments on research evidence whenever possible, rather than relying on expert opinion, anecdotal evidence, case reports and tradition. 3–5 The approach was likely started by Archie Cochrane, a Scottish physician and epidemiologist and his influential book, Effectiveness and Efficiency: Random Reflections on Health Services. Evidence-based practice means integrating the best available clinical research evidence with individual clinical expertise 1,2 and is the dominant approach used in medicine and becoming increasingly important in allied professions, including optometry.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |