The data for this study were acquired from the Scopus database without defining the analysis period. The search started on January 21, 2023, and contained all articles with terms using the Medical Subject Headings (MeSH) combination: (geriatrics AND gerontology AND elderly OR older AND adult) AND (LIMIT-TO (DOCTYPE, "ar") OR LIMIT-TO (DOCTYPE, "re")). This strategy enabled a broader and interdisciplinary analysis of geriatrics and gerontology. Therefore, these keywords were used such that the maximum number of relevant publications were incorporated into the extracted data.

All data from the Scopus database, including article information, such as author names, titles, journals, keywords, institutional affiliations, citations, and abstracts, were downloaded. All data were imported into a Microsoft Excel file (xls format) to check for data errors. Then, all downloaded data were filtered by the inclusion criteria, as follows: (1) open access (OA) publications (all OA publications were included); (2) papers published as articles; and (3) articles published in English. The corresponding authors of the present study, LSSN and NBO, reviewed the titles of all articles for inclusion in the analysis. Any differences between them were discussed and resolved by a third author. Duplicate documents were defined as articles with the same title, authors, and year and were identified using Microsoft Excel software. In recent years, the importance of OA for authors has been heightened by the policies of major research funders in many countries, which have required that publications arising from funded work be freely available to all.

Scientometrics is involved in productivity analysis and the measurement of scientific fields. The quantitative assessment of publication productivity through scientometric parameters is a reliable technique used to understand the impact of any research on a community.^16,17) We explored global publications related to geriatrics and gerontology through the quantitative metrics of scientometrics and bibliometrics. OA articles were analyzed. The large increase in subscription rates for conventional subscription-based journals and traditional publication editions led to the formation of the Open Access Academic Communication Movement. In this study, we used Microsoft Excel version 2019 (v16.0) and VOSviewer (v1.6.18; https://www.vosviewer.com/) to describe the basic characteristics of the publications, countries, institutions, keywords, and citations. VOSviewer uses text mining functions and advanced visual analysis to perform co-occurrence analyses.¹⁸⁾ Co-occurrence analysis helps quantify common information in various data, revealing the association between content and common information relations.¹⁹⁾ The types of co-occurrence analysis research are broad, including co-country, co-institution, co-keyword, and co-citation analyses. After searching the literature, we extracted publication dates, journals, countries, institutions, and keywords using Microsoft Excel. The analysis was then separated into three stages: (1) a descriptive statistical analysis of the growth patterns, numbers, years, institutions, countries, and main journals of the publications; (2) a co-occurrence analysis of keywords using VOSviewer; and (3) a co-citation analysis to rank the most influential articles in this field.

The results and discussion are presented together for clarity. The topics include survey status, hotspots and co-institutions, survey hotspots, and top topics.

This study complied the ethical guidelines for authorship and publishing in the Annals of Geriatric Medicine and Research.²⁰⁾

The 858 articles analyzed from the Scopus database, published between 1965–2022 confirmed the trend of increasing research publications in geriatrics and gerontology (Fig. 2). Interdisciplinary research in geriatrics and gerontology has become more widespread, thus promoting a wide range of more in-depth research.²¹⁾ In the last 8 years (2014–2022), referred to as the “prosperity” period, global publications in this field have increased, indicating gradually increasing attention from scholars, a growth trend that is expected to continue. We consider this period to be the “perfect storm,” in the sense that the aging of the population advances quickly and dynamically, together with the availability of new instruments, procedures, methods, and technologies to drive the development of research in geriatrics and gerontology. A bibliometric study by Ang et al.²²⁾ reported that geriatrics and gerontology are new research areas, as no journals have published more than 10,000 articles. This reinforces the need for greater investments from public and private institutions and researchers to consolidate this field of study.

The articles were published in a total of 340 journals. The two journals with the largest contributions were from the clinical area of geriatrics; however, most journals had more interdisciplinary scopes, with contributions from various disciplines, especially in health and social and educational gerontology. Among the 10 journals with the highest contributions in this study (Table 1), five are from the United States, including the Journal of the American Geriatrics Society and the Journal of the American Medical Directors Association with the highest impact factors (IF), respectively. The bibliometric analysis by Ghamgosar et al.¹⁾ on geriatric nursing also showed that these two journals published the most articles in that field. Our results showed that the listed journals are active and have high IFs based on Journal Citation Reports (JCR). In recent years, the importance of OA for authors has been heightened by the policies of major research funders in many countries, which require that publications arising from funded work be freely available.²⁾ Although the listed journals are traditional subscription-based periodicals, authors may choose to pay to have their articles published with OA, making them immediately and permanently available for everyone to read and download. Researchers can access most studies in geriatrics and gerontology by following the journals listed in Table 1.

The United States (n=378) was the leading country in geriatrics and gerontology research, followed by Japan (n=127), Canada (n=79), the United Kingdom (n=34), and Germany (n=32). We observed a stable cooperative relationship between North America and Europe as well as in Asian countries such as Japan and South Korea. The institutions listed in Fig. 3 illustrate the partnerships and cooperation between those actively publishing in the fields of geriatrics and gerontology. Xiao et al.²³⁾ identified the economy as one of the main factors affecting the productivity of countries. Additionally, countries with high rates of population aging, such as Japan and European countries, are also significant contributors of research on older adult populations, especially those aged ≥80 years.²⁴⁾ We observed that the keyword “80+ elderly” was cited 461 times, confirming that these countries are also studying older adult individuals in this age group.

In the co-citation analysis, the article by Jerome A. Yesavage, MD, published in 1988, titled “The Geriatric Depression Scale” (GDS) was the most cited (n=478) (Table 2). We believe that this study made important contributions to the development of this research field. Krishnamoorthy et al.²⁵⁾ described the GDS as one of the most commonly used instruments to track and detect older adults with or at risk of depression, which is a public health problem. These data are consistent with the results of our analysis of the frequency of occurrence of the 20 main keywords (Table 3) and our identified key terms such as geriatric assessment, psychological aspects, depression, and risk factors.

Classification of the studies in Table 2 by macro-themes revealed three themes: cognitive assessment (articles #1, #3, #7, and #10), functional capacity (articles #2, #4, #5, and #9), and frailty (articles #6 and #8).

We analyzed 5,278 keywords. The analysis of research hotspots showed that the main global research topics in geriatrics and gerontology were older adults (n=663), education and training (educational research) (n=471), and older adults aged ≥80 years (n=461). These hotspots gradually expanded to include care for older adults through geriatric assessments (n=395), geriatric nursing (n=367), and procedures and management (n=308) (Table 3, Fig. 4). Topics related to mental health, classified into sub-areas such as psychiatry and psychology, as well as the macro-theme of functional capacity, were also research hotspots in geriatrics and gerontology. These themes were also frequently reported in other bibliometric analyses.^13,23)

In contrast, the term dementia, which was prominently featured in the studies above, appeared in only 44 articles in the co-occurrence analysis; we attribute this contrary finding to the choice of database and search strings. However, the analysis of the co-occurrence of the term dementia with the term “oldest-old” (80+) (n=44 publications) showed that 73% of studies on dementia focused on elderly people aged ≥80 years; thus, it seemed to be a research topic.²⁶⁾ Original studies (n=178), reviews (n=93), and epidemiological prevalence studies (n=52) appeared to be more commonly reported by researchers in geriatrics and gerontology.^27-29)

The burst analysis of keywords did not reveal a drastic pattern of change in the searches for geriatrics and gerontology (Fig. 5). The keyword “older adults” (n=663) showed the most robust growth in this field. Keywords related to the health of older adults were highlighted when analyzed on a macro-theme, such as geriatric assessment (n=395), geriatric nursing (n=367), attitudes of health personnel (n=147), depression (n=131), and prevalence (n=113) (Table 3). The keyword “older adults (80+)” also appeared at a high frequency in the included studies (n=461). A bibliometric analysis by Gonzalez-Alcaide et al.²⁴⁾ reported a significant growth in scientific studies on the population aged ≥80 years, with a focus on cardiovascular and cerebrovascular diseases, dementia, and neoplasia. Moreover, >96% of these studies were published in European, North American, and Asian countries. Therefore, this is a research hotspot in geriatrics and gerontology, enabling a vast field of research with new approaches, such as geriatric syndromes, as well as the social and psychosocial aspects of the population in this age group.