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:
Sent: Thursday, November 08, 2012
12:48 PM
To:
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.