Analysis of Publication Activity and Research Trends in the Field of Lichen Planus: Pubmed Review

Background: Currently, there is only one bibliometric study of lichen planus (LP) and oral lichen planus (OLP) in the literature, which examined the most cited articles in the Scopus database. Our study covered all published articles in the PubMed database for 140 years since, from 1880 to 2021. In addition to the classical bibliometric analysis, we conducted a lexical analysis of key terms to build research trends in the oral lichen planus. Aims: Analysis of publication activity in the field of lichen planus by countries, their economic status and population, as well as identification of concomitant diseases by lexical analysis of key terms extracted from headings and abstracts over the past 20 years. Methods: Information from the PubMed database was retrieved automatically based on a query for the period from 1880 to 2021, including the field: title, abstract, authors, and year of publication. A total of 8173 articles were retrieved. The selection of keywords and identifying trends in related terminology were done using expert and automatic methods. An analysis of publication activity by country and socio-economic indicators was carried out. With the help of neural network analysis, the most characteristic terms related to LP were identified. Common terms were ranked by occurrence in titles and abstracts. Results: Publication activity in the field of LP and OLP has especially increased in the 21st century. The United States is the most productive country. China is a leader among countries with economies in transition. India is a leader among emerging economies. LP research is distributed worldwide. Finland ranks first in the number of publications per capita. The temporal dynamics of terminology are noted, including an increase in the number of terms used in any field of science (hereinafter referred to as general scientific terms). Conclusion: Publication activity in the field of LP and OLP has increased significantly in the 21st century. The highest publication activity was observed among authors from India, the USA and China. The leaders among economically developed countries are Italy, among the countries with economies in transition - China, and among the emerging economies - India. Based on lexical analysis of key terms, the following concomitant diseases were identified: carcinoma, leukoplakia, hepatitis, and lupus.