Elsevier is developing Scopus, an online STM bibliographic database service, due for release in Q4 2004.

It will compete head-on with Thomson ISI's Web of Science. A pre-release version is expected to be unveiled later this month.

Scopus has been in beta testing for several months at a range of university libraries in the US, Canada and Europe, including Pepperdine, Toronto and Oxford.

Elsevier is making the site available for free until May in return for intensive feedback on usability.

A Pepperdine notification claims that Scopus will cover 13,000 international journals from more than 4,000 publishers with five years of back reference.

It will offer access to an estimated 80% of peer-reviewed scientific literature, and lay claim to being the world's largest scientific, technical, medical and social science database (although ISI Web of Science, with back files to 1945 and 8,500 journals, will dispute such claims).

Scopus is also expected to benefit from technology developed across a range of Elsevier online services, including science search engine Scirus, bibliographic database Embase and aggregation service Engineering Information.

Thomson ISI, meanwhile, has upped the stakes in this new power game for market dominance by announcing a collaboration with NEC to create a comprehensive multidisciplinary web citation index.

It will adopt Elsevier's customer-facing tactics by conducting a pilot programme this year, in preparation for launch in 2005.

Significantly, the Thomson-NEC service will embrace citations and index links to open access publications - something that Elsevier is unlikely to favour.

"Our mission remains to provide researchers with access to the highest quality content, no matter what medium or business model supports it," said James Pringle, Thomson VP of development.

www.scopusnet.com