Background: Funding of drug studies by the pharmaceutical industry is associated with outcomes that are favorable to the funder. Consumers are likely to be unaware of this potential for bias. Authors of Cochrane reviews must declare conflicts of interest, but there appears to be no policy regarding disclosure of the funding sources of trials included in a drug review, though this is just as important. Such critical information should be included the plain language summaries because the majority of consumers are likely to read no further. Plain language summaries are a 400-word departure from the much shorter "consumer summaries" that were the standard for many Cochrane reviews. In June 2005, changes were introduced in the Cochrane handbook that improved the preparation of plain language summaries. Consumers who read abstracts on the Cochrane Web site or who find them incidentally while conducting Internet searches would eventually have free access to a clearly written, lay language summary of the newer Cochrane Reviews.
Objectives: We wanted to know whether the plain language summaries of the latest Cochrane drug reviews identified the funding sources for the included trials.
Methods: A survey of all drug reviews published in the Cochrane Library between Issue 3, 2005 and Issue 2, 2007 was conducted to determine whether trial sponsorship is noted in the plain language summary. We did not expect each trial's sponsorship to be identified, but we did look for, at very least, a brief mention of the proportion of trials funded by industry.
Results: Of 200 drug reviews, none mention trial funding in the plain language summary.
Conclusion: As more and more drug trials are funded by the pharmaceutical industry, trial results-and in turn Cochrane drug reviews-may be distorted accordingly. Plain language summaries are intended as stand-alone documents. Disclosure of clinical trial funders is crucial to providing complete information.