UMLS at 30 years, how is it used and published?---A systematic review (Preprint)
BACKGROUND Background: The unified medical language system (UMLS) has been a critical tool in biomedical and health informatics, and the year 2020 marks the 30th anniversary of UMLS. Despite its longevity, there is no systematic review on UMLS, in general. Thus, this systematic review was conducted to provide an overview of UMLS and its usage in English-language publications in the last 30 years. OBJECTIVE Objectives: The objective is twofold: to provide a comprehensive and systematic picture of the themes, their subtopics, and the publications under each category and to document systematic evidence of UMLS and how it has been used in English-language publications in the last 30 years. METHODS Methods: PubMed, ACM Digital Library, and Nursing & Allied Health Database were used to search for literature. The primary literature search strategy was as follows: UMLS was used as a MeSH term or a keyword or appeared in the title or abstract. Only English-language publications were considered. RESULTS Results: A total of 943 publications were included in the final analysis. After analysis and categorization of publications, UMLS was found to be used in the following emerging themes: natural language processing (NLP) (230 publications), information retrieval (125 publications), terminology study (90 publications), ontology and modeling (80 publications), medical subdomains (76 publications), other language studies (53 publications), artificial intelligence tools and applications (46 publications), patient care (35 publications), data mining and knowledge discovery (25 publications), medical education (20 publications), degree-related theses (13 publications), and digital library (5 publications) as well as UMLS itself (150 publications). CONCLUSIONS Conclusions: UMLS has been used and published successfully in patient care, medical education, digital libraries, and software development, as originally planned, as well as in degree-related theses, building artificial intelligence tools, data mining and knowledge discovery and more foundational work in methodology and middle layers that may lead to advanced products. NLP, UMLS itself, and information retrieval are the three themes with the most publications. The review provides systematic evidence of UMLS in English-language peer-reviewed publications in the last 30 years.