The number of distinct new biomedical citations indexed per month by CiteULike and by MEDLINE. The figure illustrates the increasing rates of growth, per month, of new citations with PubMed identifiers to be indexed by MEDLINE (upper points in pink) and tagged by users of CiteULike (lower points in blue). The numbers for MEDLINE were estimated by taking the reported yearly totals and dividing by 12. The numbers for CiteULike were measured directly from a database export.
Good et al. BMC Bioinformatics 2009 10:313 doi:10.1186/1471-2105-10-313