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Here is an example for advanced learners. This systematic review could be flagged as "level 1 evidence" showing reduction in mortality for women < 60 years old using some traditional critical appraisal criteria but has serious flaws upon further evaluation. * HRT not associated with significant effect on overall mortality * based on systematic review and meta-analysis of 30 randomized trials with 26,708 women * Reference - J Gen Intern Med 2004 Jul;19(7):791 <http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&li st_uids=15209595&dopt=Abstract> full-text <http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedi d=15209595> , editorial can be found in J Gen Intern Med 2004 Jul;19(7):810 <http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&do pt=Abstract&list_uids=15209598> full-text <http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedi d=15209598> , commentary can be found in BMJ 2005 Jan 1;330(7481):filler <http://www.bmj.com/cgi/content/full/330/7481/0-f> , ACP J Club 2005 Jan-Feb;142(1):1 <http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&do pt=Abstract&list_uids=15656542> , J Gen Intern Med 2005 Feb;20(2):212 <http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&do pt=Abstract&list_uids=15836558> full-text <http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedi d=15836558> * DynaMed commentary -- conclusion of lower mortality in women aged < 60 years in this review not considered valid because * analysis was based on 4,141 women in trials with mean age < 60 years * analysis did not include 5,522 women aged 50-59 years in WHI trial (which had mean age 63 years) * analysis with WHI trial would find no difference in mortality * DynaMed commentary -- entire meta-analysis fundamentally flawed by weighting studies based on number of deaths instead of sample size * for example consider the meta-analysis of trials with mean age < 60 years which included 17 trials and 4,141 women * 1 trial with high mortality in 130 ovarian cancer patients provided 3% of the overall sample size but was calculated as providing 41% of the weight in this meta-analysis * similar conclusions for outcome of coronary heart disease events (reduced risk in women < 60 years old) reported in meta-analysis of 23 trials with 39,049 women conducted by same authors (J Gen Intern Med 2006 Apr;21(4):363 <http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&do pt=Abstract&list_uids=16686814> ) but similar methodologic flaws limit validity of conclusion (DynaMed commentary) --------------------------- Brian S. Alper, MD, MSPH Editor-in-Chief, DynaMed (www.DynamicMedical.com) Medical Director, EBSCO Publishing 10 Estes St. Ipswich, MA 01938 office (978) 356-6500 ext 2749 cell (978) 804-8719 fax (978) 356-6565 home (978) 356-3266 "It only takes a pebble to start an avalanche." This e-mail and any attached files transmitted are confidential and solely for the use of the intended recipient. It may contain information which is covered by professional or other privilege. If you are neither the intended recipient of this e-mail nor the person responsible for delivering it to the intended recipient, be advised that you have received this e-mail in error and that any use of it is strictly prohibited. Please notify the sender immediately be reply e-mail and then delete from your system. EBSCO Industries, Inc., its subsidiaries and divisions, accept no responsibility for any loss or damage suffered by any person arising from the use of this e-mail. -----Original Message----- From: Evidence based health (EBH) [mailto:[log in to unmask]] On Behalf Of Terry Shaneyfelt Sent: Thursday, September 25, 2008 2:32 PM To: [log in to unmask] Subject: examples of bad articles for teaching Does any one have a good example of a fairly flawed therapy article for a course that I teach in EBM. Seems most of the articles I find arent too badly designed. Students always want to see some bad articles to critique. Thanks in advance