Publication Output, by Field of Science

A region’s, country’s, or economy’s distribution of publications by field of science can indicate their research priorities and capabilities. Health-related research, which includes health sciences plus biological and biomedical sciences, is the largest global field of science (36% of publications) (Table S5a-17). In the United States and EU, health-related research and engineering are the largest scientific fields. In China, the largest research area is engineering (25%) followed closely by health-related research (23%); computer and information sciences (13%) is a distant third (Figure 5a-4). Japan has a portfolio with health-related research (43%) at the top followed by engineering (15%) and physics (13%) (Figure 5a-4).

S&E research portfolios by seven largest fields of science by selected region, country, or economy: 2018

EU = European Union.

Note(s)

Articles refer to publications from a selection of peer-reviewed journals and conference proceedings in S&E fields from Scopus. Articles are classified by their year of publication and are assigned to a region, country, or economy on the basis of the institutional address(es) of the author(s) listed in the article. Articles are credited on a fractional-count basis (i.e., for articles from multiple countries, each country receives fractional credit on the basis of the proportion of its participating authors). Data are not directly comparable to Science and Engineering Indicators 2018; see Technical Appendix section on data filters. See Table S5a-1 for countries included in the EU. See Table S5a-17 for all fields of science. See Table S5a-2 through Table S5a-16 for source data.

Source(s)

National Center for Science and Engineering Statistics, National Science Foundation; Science-Metrix; Elsevier, Scopus abstract and citation database, accessed June 2019.

Science and Engineering Indicators

Scientific Field Concentrations Across Regions, Countries, and Economies

The specialization index allows for the comparison of research concentration or focus areas among regions, countries, and economies. The specialization index normalizes a country’s share of output in a field of science with the total global share of output in that field (Science-Metrix, 2018). For example, astronomy and astrophysics articles comprised 0.8% of the U.S. S&E publication output (Table S5a-17). Normalizing the 0.8% by the world average of 0.5% in that field shows the U.S. specialization index for astronomy and astrophysics is 1.6, which is above the world average of 1.0 (Table S5a-17 and Table S5a-19). The specialization index also permits comparison across countries, revealing that the U.S. concentration is on par with several other countries but below that of Chile (5.5) (Table S5a-19), which houses many of the world’s leading observatories.

Figure 5a-5 shows fields (blue) where the region, country, or economy has a concentration above the world average. The figure reveals that the United States has above-average concentrations in psychology (2.0), astronomy and astrophysics (1.6), social sciences (1.6), health sciences (1.4), biological and biomedical sciences (1.2), and geosciences (1.2). The EU has similar focus areas as well as mathematics and statistics (1.1) and natural resources and conservation (1.0). The concentration areas for China show more focus in chemistry (1.6), materials sciences (1.6), engineering (1.5), natural resources and conservation (1.3), computer and information sciences (1.2), physics (1.1), and agricultural sciences (1.1). Researchers find that G7 countries emphasize the life sciences while BRIC countries focus on physics, chemistry, mathematics, and engineering (Yang et al. 2012).

Specialization of S&E articles by field by region, country, or economy: 2018

EU = European Union.

Note(s)

World index value is 1.00 for all fields. Articles are classified by their year of publication and are assigned to a region, country, or economy on the basis of the institutional address(es) of the author(s) listed in the article. The specialization index (SI) is calculated as follows: SI = (Fe/Te)/(Fw/Tw), where Fe is the fractional count of a given region, country, or economy's output in a given field (F) divided by the total output for the region, country, or economy (Te); this is divided by the total output of the world in a given field (Fw) divided by the total output across all fields at the world level (Tw). The English-language bias of the Scopus database may impact the SI for psychology and social sciences (see Technical Appendix for more information). Geosciences includes geosciences, atmospheric sciences, and ocean sciences. See Table S5a-18 through Table S5a-31 for data about other countries and from 2000–18. See Table S5a-1 for countries included in the EU.

Source(s)

National Center for Science and Engineering Statistics, National Science Foundation; Science-Metrix; Elsevier, Scopus abstract and citation database, accessed July 2019.

Science and Engineering Indicators

The U.S. specialization index scores have increased from 2008 to 2018 for astronomy and astrophysics, geosciences, health sciences, and psychology (Figure 5a-6). The 18% increase in the health sciences index from 2008 to 2018 demonstrates the increasing concentration of the United States in health sciences and aligns with federal spending patterns in life sciences (see Figure 4-11 "Federal obligations for research, by agency and major S&E field: FY2017" in the forthcoming Indicators 2020 report Research and Development: U.S. Trends and International Comparisons).

U.S. specialization of S&E articles, by field: 2008 and 2018

Note(s)

Articles are classified by their year of publication and are assigned to a region, country, or economy on the basis of the institutional address(es) of the author(s) listed in the article. The specialization index (SI) is calculated as follows: SI = (Fe/Te)/(Fw/Tw), where Fe is the fractional count of a given region, country, or economy's output in a given field (F) divided by the total output for the entity (Te); this is divided by the total ouput of the world in a given field (Fw) divided by the total output across all fields at the world level (Tw). Geosciences includes geosciences, atmospheric sciences, and ocean sciences. Data for additional years are available in Table S5a-18 through Table S5a-31.

Source(s)

National Center for Science and Engineering Statistics, National Science Foundation; Science-Metrix; Elsevier, Scopus abstract and citation database, accessed June 2019.

Science and Engineering Indicators