Table 5-30
Citation of S&E literature in U.S. patents relative to share of S&E literature, by selected field and country/region: 2002
Relative citation index
Field and country/region
of citing inventor
All fields 1.23 0.69 0.64
Clinical medicine 1.19 0.69 0.65
Biomedical research 1.30 0.65 0.50
Chemistry 1.59 0.72 0.55
Physics 1.25 0.55 1.05
Engineering/technology 1.15 0.71 0.69
NOTES: Relative citation index is the frequency of citation of a country or region's S&E literature by U.S. patents, adjusted for its world share of S&E articles. Citations of the country's own literature are excluded. An index of 1.00 would indicate that the region's share of cited literature was equal to its world share of S&E literature. An index greater or less than 1.00 would indicate that the region was cited relatively more or less frequently than indicated by its share of world S&E literature. Citations are references to S&E articles in journals indexed and tracked by the Institute for Scientific Information's Science Citation Index and Social Sciences Citation Index. Citation counts are based on a 6-year window with a 2-year lag, i.e., citations for 2002 are references made in U.S. patents issued in 2002 to articles published in 1995–2000. Scientific field is determined by CHI's classification of the journal. Computer sciences are included in engineering and technology. Patent data for 2002 are preliminary and subject to change.

SOURCES: U.S. Patent and Trademark Office; Institute for Scientific Information, Science Citation Index and Social Sciences Citation Index; CHI Research, Inc.; and National Science Foundation, Division of Science Resources Statistics, special tabulations.
Science & Engineering Indicators — 2004
Source Links:
Source data Excel
Close window