Why does PubMed Central contain less than the complete contents of some journals?
Most participating journals include all their content in PMC, but a few have chosen to deposit only their primary research articles. PMC also has agreements with certain publishers who deposit only those articles that fall under an open access or similar program covering selected articles from a range of journals. Examples of such programs are Blackwell Publishing’s Online Open, Oxford Journals’ Oxford Open, and Springer’s Open Choice. For such programs, PMC may have only a few articles each from a number of different journals. (Note that these partial participation journals do not appear in the PMC Journal List.) In addition, the NIH Public Access policy and the Wellcome Trust Open Access policy designate PMC as a repository for articles arising out of research funded by these organizations. Here again, PMC only has selected articles from many different journals and these journals are not included in the PMC journal list.
