HOW WELL DOES JOURNAL IMPACT WORK IN THE ASSESSMENT OF PAPERS ON CLINICAL PHYSIOLOGY AND NUCLEAR-MEDICINE

This study reports a citation analysis of 217 scientific papers on cli nical physiology and nuclear medicine published in 69 different journa ls during the years 1985-92. The actual citation frequency was compare d with the journal 'impact factor' (i.e. the average number of times a paper is cited in a particular journal in the year of publication and the subsequent year). The average impact factor per paper was 1.96 an d per journal 1.92 (range 0.0-22.8). A direct relation was found betwe en the journal impact factor and the citation factor (i.e. the actual citations in the year of publication and the subsequent year) (journal s with five or more papers R=0.69, P<0.01; all journals R=0.40, P<0.00 1). However, the citation factor was significantly below the journal i mpact factor (P<0.0001). An almost linear relation was found between c umulated citations and time (R=0.99, P<0.02-0.0001), but an initial ph ase of no citation was identified, and the number of citations per yea r reached a maximum or plateau 3-7 years after publication, which was later than the general maximum of 2-3 years for all medical specialiti es. In a sample of 200 known autocitations, 75% of the papers had full recovery, 3% mixed recovery and 22% no recovery, giving an overall re covery of 70%. In conclusion, although a phase of no citation was iden tified, which gave a lower citation factor than the journal impact fac tor, the citation frequency increased over time, and altogether there seems to be a good agreement between journal impact factor and overall citation frequency of papers on clinical physiology and nuclear medic ine.