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Applied Evidence
Of mites and men: Reference bias in narrative review articles
Lasse M. Schmidt, MD Peter C. Gøtzsche, MD Nordic Cochrane Centre, Copenhagen, Denmark
One of the authors of this article is also author of the Cochrane review on house dust-mite control measures for asthma that we used as our index review. Financial support from the Danish Medical Research Council. The abstract of this paper was presented as a poster at the 11th International Cochrane Colloquium, Barcelona, October 26–31, 2003.
We conclude that narrative review articles on house dust mites and asthma are severely biased in their selection of references and very unreliable in their intervention recommendations. This finding may be generalizable, since there is no reason to believe that physicians specializing in asthma should be more biased than others1-3 when they write reviews.
CORRESPONDING AUTHOR Peter C. Gøtzsche, MD, DrMedSci, Nordic Cochrane Centre, Rigshospitalet, DK-2100 København Ø, Denmark. E-mail: pcg@cochrane.dk.
