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Re-sending without the attachment as the list rejects, but you can download from the link, Tom. Senior Research Fellow in Public Health & Lecturer in EBM CSFM, School of Medicine, University of Crete Skype: elenapetelos ---------- Forwarded message ---------- From: Petelos, E. <[log in to unmask]> Date: Thu, Apr 27, 2017 at 12:36 PM Subject: Re: Systematic reviews, what am I missing? To: Tom Jefferson <[log in to unmask]> Cc: [log in to unmask], "Dr E. Petelos" < [log in to unmask]> Hi, Tom. I had just downloaded it, actually. Link for PDF and attached file. https://oup.silverchair-cdn.com/oup/backfile/Content_public/ Journal/bmb/121/1/10.1093_bmb_ldw058/6/ldw058.pdf?Expires=14 93634717&Signature=hFmOpdsWHM2mSwKTdIUDQ1moL6hyB-AxadbNcLoHr M7HWZjzE5JhdINz51WZIUKW5iJTLXFok6WuJ8Zvpl4DO2UH6ebWl6KEZhjqn nVaX-SEy~6A-oKd9czUwjeabF7Bd48rzWxuRMzlBBo-Pguia8qBHNPxfKVRO dgRwpR1nmdKT~4hpRuGLRY~JV9H5kTiHi6BB88~639zjuDknh-WNHJj6nNDg SNgsxSy8tgkJG2GQiUPzH~NPeElgvlYFf24Y5BCHBocfVI8WgY4m9xHSUP8O zD5ZB9T4vTNHcXShhSyzlwIqtXOUT6fmBkgvw2SFo4lrOtNxHq8jI26HYXk0 w__&Key-Pair-Id=APKAIUCZBIA4LVPAVW3Q Kind regards Elena On Thu, Apr 27, 2017 at 12:30 PM, Tom Jefferson <[log in to unmask]> wrote: > Norman, could you please send a pdf of the paper? > > Thanks, > > Tom. > > Dr Tom Jefferson > Senior Associate Tutor > University of Oxford > Oxford OX2 6GG > > On 27 April 2017 at 11:28, Norman Vetter <[log in to unmask]> wrote: > >> We have recently published a review on the ethics of reporting all the >> results of clinical trials: >> >> https://academic.oup.com/bmb/article/121/1/19/2926156/The-et >> hics-of-reporting-all-the-results-of >> >> Norman Vetter >> >> On 27 April 2017 at 09:59, Jon Brassey <[log in to unmask]> >> wrote: >> >>> Stimulated by a recent paper on stem cells ( >>> http://www.cell.com/stem-cell-reports/pdf/S2213-6711%2817%2930119-4.pdf) >>> reported that nearly half of stem cells trials aren't reported. This falls >>> in the range of OpenTrials which report 30-50% of trials aren't reported. >>> It got me thinking: >>> >>> - Many trials are unpublished. >>> - Even Cochrane (one of the better SR publishers) does a poor job of >>> handling unpublished studies (eg http://www.bmj.com/content/346 >>> /bmj.f2231) >>> - Only including published trials can have a profound effect on the >>> outcome of a systematic review (e.g. http://www.nejm.org/doi/full/1 >>> 0.1056/NEJMsa065779 & http://www.bmj.com/content/344/bmj.d7202) >>> >>> Further. a couple of definitions of systematic reviews: >>> >>> 1) A Brief History of Research Synthesis EVALUATION & THE HEALTH >>> PROFESSIONS, Vol. 25 No. 1, March 2002 12-37 >>> *SYSTEMATIC REVIEW The application of strategies that limit bias in the >>> assembly, critical appraisal, and synthesis of all relevant studies on a >>> specific topic. Meta-analysis may be, but is not necessarily, used as part >>> of this process.* >>> >>> 2) Cochrane's >>> <http://www.cochranelibrary.com/about/about-cochrane-systematic-reviews.html> >>> *A systematic review attempts to identify, appraise and synthesize all >>> the empirical evidence that meets pre-specified eligibility criteria to >>> answer a given research question. Researchers conducting systematic reviews >>> use explicit methods aimed at minimizing bias, in order to produce more >>> reliable findings that can be used to inform decision making.* >>> >>> The first definition would suggest - as it states '*all relevant >>> studies*' - that most systematic reviews are not really systematic >>> reviews as they miss lots of trials. >>> The second definition is more flexible by saying "*..attempts to >>> identify, appraise and synthesize...*". It's more flexible as it's not >>> saying '*all*' merely that you '*attempt*' to identify all the >>> evidence. >>> >>> So, two questions to the group: >>> >>> >>> - Based on the first definition, are systematic reviews that don't >>> include 'all relevant studies' not actually systematic reviews? >>> - Based on the second definition, any clue as to how hard one should >>> 'attempt' to locate all the evidence? For instance, systematic >>> reviews tend to try to locate ALL published journal articles and - >>> generally - a fairly poor attempt at unpublished trials, who decided that >>> and is it evidence based? >>> >>> I look forward to hearing from you all. >>> >>> Best wishes >>> >>> jon >>> >>> -- >>> >>> Jon Brassey >>> Director, Trip Database <http://www.tripdatabase.com> >>> Honorary Fellow at CEBM <http://www.cebm.net>, University of Oxford >>> Creator, Rapid-Reviews.info >>> >>> >> >> >> >> -- >> Norman Vetter >> Web page: www.normanvetter.com >> > >