Kat measures the cream

Another week, another bunch of scientists strutting their stuff across your bibliometrics column ("Top 20 countries in clinical medicine based on citations per paper", 17 April). Complex beast, yes, but is single-number non peer-review arts research assessment a chimera? Enter the Kat-index, inspired by the University of California's Jorge Hirsch, who in 2005 launched the H-index (based on Thomson ISI). The Kat-index is transparently based on a widely available academic database, WorldCat, and compresses an individual's total research achievement into a single number. Unlike the H-index, it is an arts-friendly cumulative measure of lifetime publications impact.

To calculate your Kat-index, search your author name(s) on WorldCat.org. This brings up a list of your publications, ranked by the number of academic libraries in which each is held. Now scroll down to the first of your publications held in at least 100 libraries, and then scroll up to the first one held in at least 200 libraries, then up to the first one held in at least 300 libraries, 400 libraries and so on. Add the total number of your publications listed to the highest number of 100s in the unbroken sequence et voilà - your Kat-index.

As the RAE's successor takes shape, perhaps the Kat-index may be embraced - perhaps even by Times Higher Education's bibliometrics column - as a flawed but meaningful supplement to the research impact arsenal's most powerful tool: informed peer review.

M.A. Katritzky, The Open University.