Underreporting of conflicts of interest in clinical practice guidelines: cross sectional study

Article type
Authors
Bindslev JBB1, Schroll JB1, Gøtzsche PC1, Lundh A1
1The Nordic Cochrane Centre, Denmark
Abstract
Background: Conflicts of interest may affect recommendations in clinical guidelines and disclosure of such conflicts is important. However, not all conflicts of interest are disclosed.

Objective: To determine the prevalence and underreporting of conflicts of interest among authors of clinical guidelines on drug treatments.

Methods: We included up to five guidelines published from July 2010 to March 2012 from each Danish clinical specialty society. Using the disclosure list of the Danish Health and Medicines Authority, we identified author conflicts of interest and compared them with the disclosures in the guidelines. For each guideline we extracted information on guideline development.

Results: We included 45 guidelines from 14 specialty societies. Of 254 authors, 135 (53%) had conflicts of interest, corresponding to 43 of the 45 guidelines (96%) having one or more authors with a conflict of interest. Only 1 of the 45 guidelines (2%) disclosed author conflicts of interest. The most common type of conflict of interest (83 of the 135) was being a consultant, an advisory board member or a company employee. Only 10 guidelines (22%) described the methods used for guideline development, 27 (60%) used references in the text and 11 (24%) graded the types of evidence behind specific recommendations.

Conclusions: Conflicts of interest were very common, but disclosures were very rare. Most guidelines did not describe how they were developed and many did not describe the evidence behind specific recommendations. Publicly available disclosure lists may assist guideline issuing bodies in ensuring that all conflicts are disclosed.