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Jadad scale has 3 items: a) was the study randomized?, b)was the study double blind?, c)was there a description of droup-outs and withdraws? If all 3 get yes, then it has 3 point. If it is described the allocation concealment method (that Brian mentioned), and it is right, then an extra point is given, the same for blinding. However, if allocation concealment and blinding are wrong, a point is taken from each item. So it goes from 0 up to 5 points. I guess abstracts cannot get more than 2 points on average, but I am not sure if the full text can get much more(!?). Jadad did not claim the scale could access validity of the paper, but to measure the likelihood of bias. however, as we are using abstracts to exclude the whole paper, then the specificity of the scale has to be very high, if compared to the gold standard that would be the appraisal of the full text. Well, in doing so we can say how much confidence can be put on an abstract. Then, clinician, students and ourselves may get something better to relay on than the pub date, or size of the trial (as Jon pointed and is true), when reading abstracts in absence of the full text. Roger ----- Original Message ----- From: "Brian S. Alper MD, MSPH" <[log in to unmask]> To: <[log in to unmask]> Sent: Saturday, July 16, 2005 9:59 PM Subject: Re: Critically appraising abstracts > At 12:00 AM 7/17/2005 +0100, you wrote: >>Concerning Jon's idea of appraising abstract, I thing Jadad's scale may be >>applied to abstracts and checked against the score of the full report. >>What do you think of it, Jon? > > > Isn't allocation concealment a major part of the Jadad scale? > > Abstracts rarely report on allocation concealment. (Full-text still does > not report on allocation concealment frequently as well.) > > There are many times where the full-text article will have flaws not > apparent in the abstract, or have information that invalidates statements > in the abstract. Some of the worst examples are "randomized" trials that > were randomized by having the first 50 patients treated one way and the > next 50 patients treated a different way. Also, outcome measures may not > be clearly understood without the full-text. > > There are times when a clinician might need to make decisions and only > have abstracts available. One must realize during those times that there > is insufficient information to be certain about the validity suggested by > the abstract. But the clinical reality is we often have to use our > judgment with uncertain information. > > The purpose of critically appraising abstracts and comparing that with the > full-text reports could be to document and publish how often important > discrepancies occur. I'm guessing that is what Roger was suggesting. > > Brian S. Alper MD, MSPH > Editor-in-Chief, DynaMed (http://www.DynamicMedical.com) > Founder and Medical Director, Dynamic Medical Information Systems, LLC > 3610 Buttonwood Drive, Suite 200 > Columbia, MO 65201 > (573) 886-8907 > fax (573) 886-8901 > home (573) 447-0705 > "It only takes a pebble to start an avalanche." > _______________________________________________________ Yahoo! Acesso Grátis - Internet rápida e grátis. Instale o discador agora! http://br.acesso.yahoo.com/