German medical faculties in the 1990s: on-line bibliometric analysis

Data of publication output from 1993 to 2001 and of observed citation impact relating to citing years 1995 to 1999 were retrieved on-line from the German host DIMDI. Expected citation data (for 1995 to 2002) were calculated using the journal impact factors supplied by ISI's Journal Citation Reports (JCR). For journals not included in the JCR, impact factors were constructed according to the number of citations received from journals indexed in ISI databases. During the investigated timespan a considerable increase in absolute counts of published papers and observed and expected citations and in relative citation rates can be seen. Observed and expected citation rates are highly correlated. Analysis of subfield-normalised citation rates reveals that with time (i) an increasing number of faculties perform above world citation average in an increasing number of subfields, (ii) each faculty moves to a higher level of performance relative to the world standard, and (iii) the differences in citation performance between the faculties become considerably smaller.