Hi Ahmed,
It's an interesting issue. I bet the risk of bias is high is you can't find the information whether the investigators were blinded of outcome knowledge. Mortality is the most objective outcome, but the causes of mortality can be hugely biased by knowledge of disease.
It's about blinding and lack of such. I put it in a broader perspective: I am practicing in a discipline which makes blinding not only undesirable, but actually insists that the test results should be obtained and interpreted (by the pathologists) in the context of clinical information to minimize diagnostic test error. I see this as an issue (from EBM perspective), as the value of the diagnostic tests will be biased and inflated inappropriately.
Nik Makretsov
Pathologist
________________________________
From: Evidence based health (EBH) [mailto:[log in to unmask]] On Behalf Of Ahmed Abou-Setta, M.D.
Sent: Thursday, November 08, 2012 12:48 PM
To: [log in to unmask]
Subject: Author Bias and Objective Outcome Measures
Hello,
I am looking into the issue of 'author bias' especially with the reporting of 'objective outcomes' (e.g. mortality). I know that bias from known sources like sponsorship (e.g. pharmaceutical industry) has been well investigated, but about just purely 'author bias'. Often authors are biased one way or another for a vast number of reasons including but not limited to personal beliefs of efficacy/effectiveness, prior observations in clinical practice, etc. I am looking for publications which measure or test this bias especially for objective outcomes since it's much easier to bias subjective outcomes (e.g. pain scores) than objective ones (e.g. mortality) especially if the trials were randomized.
Thanks.
Ahmed
P.S. Here is the search strategy I used in PubMed: ("bias (epidemiology)"[MeSH Terms] AND (prejudice[MESH] OR Conflict of Interest[MESH])) NOT Letter [Publication Type]. It yielded some interesting citations but nothing hit the nail on the head.
