The results of the panel's citation analyses are shown in Figure 2.4 and Table 2.2. As shown in Figure 2.4, the top 3 countries for the immunology field based on percentage of the world's citations from 1981-1997 in immunology are
Another measure that can be used is relative citation impact (RCI). RCI is the country's share of the world's citations in the field, divided by its share of world publications in the field. It can be thought of as a comparison of a country's citation rate for a particular field with the world 's citation rate for the field. A relative citation impact greater than 1 shows that the country's rate for the field is higher than the world's. Some believe RCI is a measure of both the influence and the visibility of a country's research (as disseminated through publications) and it gives some indication of the quality of the average paper. As shown in Table 2.2, the top 3 countries based on relative citation index for 1981-1997 are
A bit disconcertingly, only 54% of the authors identified in the ISI Immunology the high impact citations were also cited in the survey conducted by the panel. The discrepancy can probably be attributed to flaws in the two approaches, in particular such defects in the ISI database as the exclusion of critical journals and the use of only the first author in the citations.
The results of the journal publication analysis are shown in Table 2.3-Table 2.7. US-based investigators produced about three-fourths of the immunology papers published in the journals Cell, Science, and Immunity in 1995-1997. US-based researchers contributed about two-thirds of the immunology papers published in Nature in 1995-1997. In contrast, scientists in countries other than the United States published more immunology articles in Blood than US-based researchers in those years (54% and 46%, respectively). The immunological subfield in which a international presence was especially strong was immunogenetics for the papers published in Cell and Blood. However, in Nature, Science, and Immunity, US-based researchers published more papers in immunogenetics than non-US-based researchers. The United States had more papers published in all five journals in the subfield of molecular immunology. The subfield of cellular immunology and clinical aspects were dominated by US-based researchers in all journals examined except Blood. Because of its extensiveness, only 6 months of the Journal of Experimental Medicine was analyzed, as shown in Table 2.8.