Beginning with volume 20, "Nuclear Science Abstracts" (NSA) citations, exclusive of abstracts, have been recorded on magnetic tape. The articles have been categorized by 34 elements of the citations such as title, author, source, journal, report number, etc. At the time of this report more than 130,000 citations had been stored for purposes of index preparation, information retrieval, and statistical examination. The report presents a brief introduction to the computer-based system and describes the methods used for selection and categorization of NSA materials. The global contributions to NSA based on these categorization methods are examined. Three appendices include an analysis of six top countries on the basis of individual contributions, a complete listing of journals contributing to volume 22 of NSA, and a ranking of the top 350 journals contributing to bolume 22 of NSA. (CC)