Combining commercial citation indexes and open-access bibliographic databases to delimit highly interdisciplinary research fields for citation analysis

Field delimitation for citation analysis, the process of collecting a set of bibliographic records with cited-reference information of research articles that represent a research field, is the first step in any citation analysis study of a research field. Due to a number of limitations, the commercial citation indexes have long made it difficult to obtain a comprehensive dataset in this step. This paper discusses some of the limitations imposed by these databases, and reports on a method to overcome some of these limitations that was used with great success to delimit an emerging and highly interdisciplinary biomedical research field, stem cell research. The resulting field delimitation and the citation network it induces are both excellent. This multi-database method relies on using PubMed for the actual field delimitation, and on mapping between Scopus and PubMed records for obtaining comprehensive information about cited-references contained in the resulting literature. This method provides high-quality field delimitations for citation studies that can be used as benchmarks for studies of the impact of data collection biases on citation metrics, and may help improve confidence in results of scientometric studies for an increased impact of scientometrics on research policy.