Sleep Disorders Research From 1945 to 2020: A Bibliometric Analysis

Background: The objective of the present review is to perform the 1st bibliometric analysis of sleep disorders research. Methods: The data was retrieved from Scopus in July 2020 for detailed analysis. Results: The 1st precise document about the sleep disorder was published in 1945. Till 15th July 2020, a total of 69657 documents were found in the Scopus database. Approximately eighty-two percent (57013/81.87%) of documents are published in the last twenty years (from 2001-2020). We calculated the per-year Growth Rate (GR) of publications (from 2000-onwards). The highest number of documents are published in 2019 (4337/7.90% of 57013) followed by 2018 (4249/7.74% of 57013) and 2017 (3974/7.24% of 57013). The productivity index (PI) for 1950-1960 and 2011-2020 era was found to be 100.21. We also provided the details of the top 50 countries with the maximum number of publications (from 1945 to July 2020). The top three (3) countries are the USA, with 24262 publications (34.83%), followed by UK (5566/8.0%) and Germany (4791/6.87%). We also performed the co-words analysis. Total 956643 (0.95 million) keywords were retrieved from 69657 published documents. After a critical analysis, we categorized them into different groups to show the trend in various domains. In the next phase of the study, only those documents were analyzed, which contained the phrase "sleep disorder" in the titles of the publications. Total 3626 documents were found. We calculated the per-year growth rate (GR). The continental distribution, the list of top twenty authors, sources/journals, departments or institutes, countries and research documents with highest citations are provided. By VOS viewer analysis, 6752, 36511 and 11473 terms in titles of the manuscripts, abstracts, and keywords were recorded, respectively. This may help in describing the overall trend in these publications. Conclusions: The present study provides a detailed list of top authors, departments, countries, sources, and top 20 most cited documents. The co-words analysis may help in describing the trends in the field of sleep disorders.