*2.2. Data Visualization and Analysis*

The software used in this article for scientometric analysis and visualization analysis is CiteSpace (5.6.R2). CiteSpace software is an information visualization software developed by Chen Chaomei, based on the Java language [25]. CiteSpace's theoretical basic system mainly includes five aspects: Kuhn's scientific development model theory, Price's scientific frontier theory, structural tree holes, the best information foraging theory of scientific communication, and the theory of discrete and reorganized knowledge units [26]. This article uses CiteSpace software to visualize the structure, regularity, and distribution of knowledge in the global health field, and analyze the co-citation of documents to mine the knowledge clustering and distribution of citation space. At the same time, we also performed co-occurrence analysis between other knowledge units in the global health field, such as cooperation between authors, institutions, and countries. Finally, we built a comprehensive knowledge map of global health research based on the results of scientific econometric analysis. Figure 1 shows the research framework of the article.

Some parameters and knowledge map identification methods will be involved in the results of the scientometric analysis, which will be explained uniformly here. The knowledge map shows the distance of time with warm and cold colors. When the time is closer to 2019, the colors become warmer. In the knowledge graph, the size of the nodes means the frequency of the authors, institutions, countries, and journals, and the connection between the nodes indicates that these nodes appear in the same article [27]. In general, when two or more authors (institutions, countries) appear in the same paper, it can be regarded as a scientific research cooperation relationship between these authors (institutions, countries) [28]. In the process of scientometric analysis, there are also some parameter indicators for a specific evaluation. H-index is a mixed quantitative index proposed by physicist George Hirsch of the University of California, USA, which is used to evaluate the amount of academic output and the level of the scholarly output of researchers and institutions. H-index indicates that h of the N papers published in the journal have been cited at least h times [29]. The Degree in the table indicates the number of connections between authors (institutions, countries) in the co-occurrence knowledge graph. A higher Degree value indicates more communication and cooperation between the authors (institutions, countries). Besides, intermediary centrality is an indicator that measures the importance of nodes in the research cooperation network, and the half-life is a parameter that represents the continuity of institutional research from a time perspective [25].
