*2.3. Statistical Analysis*

The results from the research were analyzed, focusing on descriptive analyses, such as the frequencies of the types of document, the language, trends in scientific publications, primary sources, the field of the publication, the leading scientific institutions, associations among nations, the primary authors in the area, and the keywords used. In the case of keywords, a normalization of the terms was carried out, as many of the main keywords had both singular and plural forms. The keywords included in the manuscript were the author's keywords. In this sense, the keywords used were not MeSH terms.

Another aspect of the analysis was the identification of networks using the VOSviewer software [40]. This open-source program was created for constructing and viewing bibliometric maps by importing the data from several sources, including Scopus [41]. The criteria used to create the maps were a minimum of 10 connections between authors, fewer than 10 authors per document, and a minimum of five authors per document. This strategy was followed for the concurrency of keywords, connections between authors, and countries.
