In a blog post entitled “Journals compliant with Wellcome mandate” (UK PubMed Central Blog, June 1, 2009), Robert Kiley noted data indicating that (for Trust-funded research papers published between October of 2007 and August of 2008) potential compliance was about 95%, but actual compliance hovered around 35%. The data were taken from slide 14/21 of a presentation that’s available via another blog post, “Funder mandates” (UK PubMed Central Blog, May 29, 2009). The potential compliance estimate of 95% is based on the percentage of journals used by Wellcome-funded authors that have a “Wellcome compliant” publishing option. The Wellcome Trust’s OA policy is available at: “Position statement in support of open and unrestricted access to published research” (last updated February 2008).
An estimate of somewhat more recent compliance can be obtained via PubMed. As noted in a NLM Technical Bulletin from the National Library of Medicine, dated May 12, 2006, the search term “wellcome trust [gr]” can be used to retrieve citations (created since June 2, 2005) indicating Wellcome Trust support.
When this search was done (on June 8), but limited to articles published in the last 1 year, the proportion of articles for which the free full text was available was: 1527/4223 = 36%. When the same search was done for articles published in the last 180 days, the proportion with free full text was: 594/2088 = 28%. So, the proportion of articles with publicly-accessible full text, published between 6 months and one year ago, can be estimated to be: (1527 – 594)/(4223 – 2088) = 933/2135, or 43.7%.
Recent compliance with the Wellcome mandate appears to be approaching 44%. Might the difference between the earlier figure of about 35% and the estimate of close to 44% be explained by articles that are publicly accessible, but not via PMC/UKPMC? Examination of a sample of 100 articles published between 6 months and a year ago (and cited by PubMed) indicated that, for about 6% of these articles, the full text was publicly-accessible only via the journal site, not via PMC. (Usually, the full text was publicly-accessible via both PMC and the journal site).
If the estimate is correct that compliance with the Wellcome mandate (Trust-funded research articles must be available through PMC/UKPMC within 6 months after publication) appears to be about (44% – 6%) = 38%, then recent compliance is close to the estimate of about 35% (see above), and still well below the estimated potential compliance figure of about 95%.
Added June 18, 2009: More extensive sampling has indicated that, for Trust-funded articles published between 6 months and a year ago (and cited by PubMed), the percentage for which the full text is publicly-accessible only via the journal site, and not via PMC, may be higher than 6%, and may be as high as 10%.