Sir

The rise of bioinformatics has focused attention on the growing depth and scope of database content. However, it is difficult or impossible given the existing citation metrics system to identify who originally created or added value to a datum. Without a system to reward, we shall continue to rely on the good will or spare time (sic) of researchers to mobilize data into the public domain.

One proposal discussed recently (http://tinyurl.com/6elpq4) concerned the building of a realistic measure for use of database elements and a 'cite me' button for a dynamic composite web page. The Global Biodiversity Information Facility (GBIF, http://www.gbif.org) is investigating the assignment of 'life-science identifiers' to allow accreditation not only to data sets, but also to the individual datum and its author. Simplified mechanisms are needed that make it easy for individuals to assign these identifiers to their data.

We believe that scientists' productivity also needs to be gauged through data publishing, which requires a culture change in the recognition of scientific output. An industry-standard identifier, such as that proposed by the GBIF, could be part of publishers' referencing systems, and authors could provide 'citation identifiers' for all data records and data sets. Such a mechanism would achieve increased data mobilization and increased accreditation, both desirable to scientists.