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Dear Juan, colleagues: just because you highlighted your statement... The concept of the hierarchy of evidence is a useful simplification. I remember that 20 y ago people were excited by appearance of the Jadad score. By using it (it is still in use, but not that frequently today) one may assign the one-number score to the study. For me it was an offense, because reminded the communist time, when 'socialist competition' e.g. between departments in a hospital was estimated by summing up the cleanness in physiotherapy department with the case fatality in the surgery. Then the next looong step The efforts to make the evaluation of the studies more accurate and detailed led to the construction of the very complicated schemes with so many details of adding +1 and subtrcting-1... that later it was almost abandoned. Some people still try to distill the fine-tuned evaluation schemes. Next the understanding that different aspects of 'quality' can not be summed up in the one index led to the multi-item scores, e.g. GRADE. I believe that it is not the final stage. In part, because people like the useful simplifications. One-dimensional scores. The SLR were put at the 'original' pyramid without lots of discussions. As I remember nobody was serious about it. There was a discussion about what to put higher - the one big rial or ensemble of the smaller trials, but it was a little bit different subject. Cutting out the SLR from the top is just step back to the 'original' pyramid, the simpler one. What is not good in the offered 'modern' one. Authors, after dropping the SLR from the top of the pyramid, 1) try to 'frame' all evidence in the SLR, and it is OK, despite it complicate the picture again, even more, than before 2) shape the 'levels' in the wave form - clear, why, but, again, making the scheme more complicated. From the teacher's point. If the tool was designed to be simple for the inoculation the students with the big idea, the simplicity is important. Trying to put the whole set of concepts into the simple scheme is a misuse of the tool. You know, that some ivory tower inhabitants even insist that the whole concept of hierarchy of the evidence is wrong (keeping it simple). Vasya On 07.12.2015 20:53, Juan Gérvas wrote: > -fully agree with you, Steve > *Claiming that the SR is futile is just as dangerous as trusting a SR > blindly.* > -exactly my point is, and i repeat again:i fully agree with the new > evidence pyramid; it is probably wrong the notion of positioning > systematic reviews on the top of the evidence pyramid > http://www.isehc.net/wp-content/uploads/2011/12/October-2015.pdf > -un saludo juan gérvas > > 2015-12-07 18:29 GMT+01:00 Steve Simon, P.Mean Consulting <[log in to unmask] > <mailto:[log in to unmask]>>: > > I'm pleasantly surprised at all the thoughtful responses so far. One > point that needs to be made strongly is that the systematic review > (SR) is often good at uncovering the limitations of systematic reviews. > > In particular, much about what we know about the biases created by > monetary conflicts of interest were discovered through SR. > > The SR is also useful at identifying research gaps, such as the > absence of lifestyle intervention trials. > > Thus, the SR is self-critical and provides us with many of the > warnings that we need to avoid placing too much faith in them. > > Nevertheless, I would not go as far as Wouter Havinga, who writes: > > > Therefore SR appear futile to me, to waste again time and money over > these numbers. It's better to ask doctors what they think would be a > good research topic then to swallow Big Pharma indoctrination. > > The SR, when tempered with our knowledge of the existing biases in > the medical literature, can still be very useful. Claiming that the > SR is futile is just as dangerous as trusting a SR blindly. > > Steve Simon, [log in to unmask] <mailto:[log in to unmask]>, Standard Disclaimer. > I'm a blogger now! http://blog.pmean.com > > Vasiliy V. Vlassov, MD President, Society for Evidence Based Medicine (osdm.org) e-mail: vlassov[a t]cochrane.ru snail mail: P.O.Box 13 Moscow 109451 Russia Phone Russia +7(965)2511021 Подпишись на новости на osdm.org -- THANK YOU for deleting my e-mail address , any other addresses, and any personal information, from this e-mail, if you plan to forward it. Also, thank you for using “Bcc” instead of “To” and “Cc“ when initiating both individual and group e-mails. These extra actions on your part help to prevent spammers and hackers from obtaining addresses and thus help prevent the proliferation of spam.