Abstract
The double-blind randomized controlled trial (RCT) is accepted by medicine as objective
scientific methodology that, when ideally performed, produces knowledge untainted
by bias. The validity of the RCT rests not just on theoretical arguments, but also
on the discrepancy between the RCT and less rigorous evidence (the difference is sometimes
considered an objective measure of bias). A brief overview of historical and recent
developments in “the discrepancy argument” is presented. The article then examines
the possibility that some of this “deviation from truth” may be the result of artifacts
introduced by the masked RCT itself. Can an “unbiased” method produce bias? Among
the experiments examined are those that augment the methodological stringency of a
normal RCT in order to render the experiment less susceptible to subversion by the
mind. This methodology, a hypothetical “platinum” standard, can be used to judge the
“gold” standard. The concealment in a placebo-controlled RCT seems capable of generating
a “masking bias.” Other potential biases, such as “investigator self-selection,” “preference,”
and “consent” are also briefly discussed. Such potential distortions indicate that
the double-blind RCT may not be objective in the realist sense, but rather is objective
in a “softer” disciplinary sense. Some “facts” may not exist independent of the apparatus
of their production.
Keywords
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Article info
Publication history
Accepted:
October 5,
2000
Received in revised form:
September 1,
2000
Received:
March 29,
2000
Identification
Copyright
© 2001 Elsevier Science Inc. Published by Elsevier Inc. All rights reserved.
