The Science Citation Index Turns 50

May 2014

In 1964, Dr. Eugene Garfield, founder of the company then known as the Institute for Scientific Information (the forerunner of the Intellectual Property and Science business of Thomson Reuters), oversaw the first release of the Science Citation Index (SCI). A groundbreaking information resource, the SCI brought to fruition Garfield’s concept of “citation indexing,” a new method for categorizing, retrieving, and tracking scientific and scholarly information. This year, the SCI—now known in its expanded, online incarnation as Thomson Reuters Web of Science—celebrates its fiftieth anniversary.

Garfield’s innovation was to break from the existing scientific indexes of the day and their dependence on standardized “subject” fields that often failed to capture the complex, cross-disciplinary nature of ongoing research. Instead, Garfield harnessed the footnotes, or cited references, that authors incorporate in scholarly publications. Each of these citations, Garfield recognized, conveys a judgment about previous work that a researcher views as significant and useful, and each establishes a cognitive link between related publications. Compiling and following citations provides an intellectual trail or thread, allowing researchers to track the progression of an idea or advancement and to identify work pertinent to their own—even, possibly, research from another discipline.

Citation indexing also offers a means of tracking the shape and evolution of knowledge itself, as citation networks reliably form themselves into distinct clusters of closely related research. Furthermore, as markers of scientific influence, citations provide an objective data point (again, based on the judgments of researchers themselves) for assessing the research impact of individuals, institutions, journals, and nations.

From its 1964 origins as a five-volume print set, through its refinement and expansion into today’s Web of Science, the SCI continues to evolve and to revolutionize access to the world’s essential knowledge.

Click here to learn more about Dr. Garfield, the history of citation indexing, and the ongoing legacy of the SCI.

The data and citation records included in this report are from Thomson Reuters Web of ScienceTM. Web of ScienceTM is a registered trademark of Thomson Reuters. All rights reserved.