Page "Cochrane Collaboration" Paragraph 25

A 2011 study done to disclose possible conflicts of interests in underlying research studies used for medical meta-analyses reviewed 29 meta-analyses and found that conflicts of interests in the studies underlying the meta-analyses were rarely disclosed.

The 29 meta-analyses included 11 from general medicine journals ; 15 from specialty medicine journals, and 3 from the Cochrane Database of Systematic Reviews.

The 29 meta-analyses reviewed an aggregate of 509 randomized controlled trials ( RCTs ).

Of these, 318 RCTs reported funding sources with 219 ( 69 %) industry funded.

132 of the 509 RCTs reported author conflict of interest disclosures, with 91 studies ( 69 %) disclosing industry financial ties with one or more authors.

The information was, however, seldom reflected in the meta-analyses.

Only two ( 7 %) reported RCT funding sources and none reported RCT author-industry ties.

The authors concluded “ without acknowledgement of COI due to industry funding or author industry financial ties from RCTs included in meta-analyses, readers ’ understanding and appraisal of the evidence from the meta-analysis may be compromised .” Noting that most assessment tools for meta-analysis do not include a domain for study funding source the authors state: “ Currently, The Cochrane Collaboration ’ s Risk of Bias tool includes an optional ' other sources of bias ' domain, which meta-analysts could use to include information on COIs.

We recommend that The Cochrane Collaboration consider formalizing the requirement to assess potential bias from COIs .”