Science Citation Index

Science Citation Index. A foundational citation index and a core component of the Web of Science platform, produced by Clarivate. It was the first systematic index to track citations between scholarly publications, revolutionizing the ability to map the structure and impact of scientific literature. Its creation introduced the concept of citation analysis, which underpins modern bibliometrics and scientometrics.

Overview

The index is a multidisciplinary database covering thousands of the world's leading scientific and technical journals. It enables researchers to trace the intellectual lineage of ideas by identifying which later publications cite a given earlier work. This functionality supports literature review, discovery science, and the assessment of a publication's influence within the scientific community. The underlying data fuels key research metrics, most notably the Journal Impact Factor, calculated annually for indexed journals.

History and development

The concept was pioneered by Eugene Garfield, an American linguist and information scientist, who founded the Institute for Scientific Information (ISI). Inspired by the Shepard's Citations legal reference system, Garfield published his seminal idea in the journal Science in 1955. The first annual printed volume was launched in 1964, covering the literature from 1961 onward. Its success led to the expansion of the citation index family with the Social Sciences Citation Index and the Arts & Humanities Citation Index. Following the acquisition of ISI by Thomson Reuters, the index was fully integrated into the digital Web of Science platform, and is now managed by its spin-off, Clarivate.

Coverage and selection criteria

Journal selection follows a rigorous editorial process managed by the Clarivate editorial team. Criteria include peer review standards, editorial board composition, publishing ethics, and the journal's international diversity. A central metric is the Journal Impact Factor, though it is not the sole determinant. The index emphasizes journals that publish original research and review articles in the natural sciences, engineering, and biomedical research. Coverage is selective, with a focus on high-impact titles, which has historically led to a strong representation of publications in English from North America and Europe.

Impact and use in research evaluation

The data has become instrumental in quantitative research assessment globally. It is used by universities, funding bodies like the National Institutes of Health and the National Science Foundation, and governments to evaluate institutional and individual research performance. Metrics derived from its data, such as the h-index and citation counts, are widely used in tenure decisions, grant applications, and university rankings like the Academic Ranking of World Universities. This reliance has also sparked significant debate within the scientific community about Goodhart's law and the limitations of reducing scholarly impact to numerical indicators.

Related products and databases

It exists within a larger ecosystem of Clarivate products. The core platform is the Web of Science, which also hosts the Social Sciences Citation Index, the Arts & Humanities Citation Index, and the Emerging Sources Citation Index. For comprehensive life sciences coverage, researchers often use the specialized MEDLINE database from the National Library of Medicine. Competitor platforms include Elsevier's Scopus and the free Google Scholar. Related analytical tools built on its data include InCites, Journal Citation Reports, and Essential Science Indicators, which provide benchmarking and trend analysis.

Category:Bibliographic databases Category:Citation indexing Category:Scientific literature