SUSTAINABLE MEDICAL INSURANCE: A BIBLIOMETRIC REVIEW

How to cite this paper: Nobanee, H., Shanti, H. Z., Abukarsh, L. S., Al Hamadi, F. Y., Abdulaziz, F., Alqahtani, A, F., AlSubaey, S. K., & Almansoori, H. A. (2021). Sustainable medical insurance: A bibliometric review [Special issue]. Journal of Governance & Regulation, 10(4), 343–352. https://doi.org/10.22495/jgrv10i4siart14 Copyright © 2021 The Authors This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0). https://creativecommons.org/licenses/by/


INTRODUCTION
Medical insurance is one of the expenses that many people across the world pay for their medical needs. There are people worldwide who cannot pay for their hospital or medical expenses, especially those who are from lower-income countries. Medical insurance significantly helps the household against the financial burden from out-of-pocket expenses (Spaan et al., 2012). It also serves to enhance the utilization of the service. Various types of medical insurance could be private or public, however, it has limited coverage of health services that do not cover all the types of illnesses, and the financial risk protection is not fully provided. There is an estimated 15 to 20% out-of-pocket total health expenditure, that was based on the report of the World Health Organization (WHO), constituting about 40% of household net income of necessary support which could significantly cause a financial disaster across the world (Doetinchem, Carrin, & Evans, 2010). When less fortunate people or those who have low incomes, suffer from an illness, the first thing they usually do is to seek a free health service from the public hospitals or nearby medical centers; however, there are only limited hospitals and centers that provide medical attention for free. This becomes the beginning of a catastrophe. People who require medical attention usually borrow money from relatives, friends, and various financial institutions to support their medical expenses, notwithstanding, some people have left no choice and remain ill, impacting their ability to work, and die.
The history of medical insurance has evolved globally, unlike before, where people, from industrialized countries, in particular, are being medically treated to the primary care physician's offices. Around 150 million people have been facing financial burdens across the world annually due to the out-of-pocket expenses for their medical-related needs (WHO, 2013). The quality of life and the wellbeing of the citizens are now the factors to determine the health status of the population of a country (Saad Andaleeb, Siddiqui, & Khandakar, 2007). Healthcare management has been one of the top subjects for observation due to the increasing costs and growing issues regarding health and wellness. As a result, various organizations in the healthcare industry have striven to enhance the safety and care quality of the patients. In addition to that, the healthcare services' accessibility and efficiency have been continuously improving to meet the demands of the customers ( We then have exported sustainable medical insurance-related English-language journal articles from Scopus and conducted a bibliometric analysis with the VOSviewer, which resulted in 638 documents. Therefore, this paper was structured to provide a comprehensive literature review on medical insurance in Section 2, followed by the methodology used to conduct the study in Section 3. Afterward, the results were demonstrated with clear analysis in Section 4 followed by a discussion of the cluster analysis in Section 5. Section 6 provides future research agenda and finally a conclusion is presented in Section 7.

LITERATURE REVIEW
According to Akachi and Kruk (2017), providing health care of high quality is a crucial element that countries should work on to achieve the Sustainable Development Goal (SDG) 3: -to guarantee healthy lives and encourage well-being for all at all ages‖ (p. 465). From the United States National Academy of Medicine's Perspectives, quality is the degree to which healthcare services delivered to people enhance required health effects (Akachi & Kruk, 2017;Baker, 2001). The main duties for quality assessments are to measure the performance of services and to calculate the difference between reality and expectations based on specific criteria and procedures. Though an absence of consensus occurs on the role of quality of care in achieving SDG 3, that is demonstrated in the lack of measures of quality that apply to lower-income situations (Akachi & Kruk, 2017).
Therefore, medical insurance is a way to improve health care quality for all citizens and to achieve sustainability. Health insurance's main function is projected to decrease the financial burden of obtaining health care services by pooling funds and distributing the risk of unexpected health events (Carapinha, Ross-Degnan, Desta, & Wagner, 2011). Health insurance coverage could raise access to care and safeguard families from the unfavorable financial impacts of ill health . According to Pan, Tian, Zhou, and Han (2016), health insurance benefits are demonstrated in the income effect and risk pooling effect. The risk pooling effect is vital for relative high-income patients, while the income effect is more essential for relative low-income patients. Various categories of social, national, private, and community-based health insurance plans exist to protect individuals from health care expenses (Carapinha et al., 2011). Therefore, this paper has focused its attention to provide a detailed analysis of medical insurance publications as it is a vital topic that has a great impact on society and will help future researchers in conducting their studies. This research was done using the bibliometric analysis approach.

METHODOLOGY
In this paper, a content analysis and a bibliometric citation analysis were used. Using Scopus and VOSviewer software, the following tests were conducted using bibliometric citation analysis: 1) citation analysis, 2) co-occurrence analysis, 3) bibliographic coupling (Nobanee, 2020).

Review sources identification
The data repository that was used in this research to extract and search for the documents is the Scopus index. The comprehensive source coverage related to physical science and medicine can be found in Scopus, as compared to the Web of Science (Mongeon & Paul-Hus, 2015). Although the Web of Science generates limited sources related to these subjects, it was argued that the database provides sources of higher qualities (

Data analysis
This paper seeks to research in the sustainable medical insurance field, which shall be done through the method of science mapping review. The bibliographic data regarding the 638 documents (articles, journals, countries, citations, affiliation, etc.) were exported on the 27th of October 2020 for the upcoming data evaluation. The keywords used to generate the documents are as follow: title (-sustainab*‖ and -health insurance‖) or (-sustainab*‖ and -medical insurance‖) or key (-sustainab*‖ and -health insurance‖) or (-sustainab*‖ and -medical insurance‖) and limit-to (doctype, -ar‖) or limit-to (doctype, -no‖) or limit-to (doctype, -re‖) or limit-to (doctype, -ed‖) or limit-to (doctype, -le‖) or limit-to (doctype, -cp‖) or limit-to (doctype, -sh‖) and limit-to (language, -English‖).
Data retrieved from the Scopus database on the subject of sustainable medical insurance showed that publications started from the year 2000 till 2020 and are still growing, Figure 1 demonstrates the trend of the topic. It is seen that in the year 2000, only 2 papers were published, and it continued at nearly the same pace with an average of 7 documents from the year 2000 until the year 2014. However, a sharp increase in the number of publications took place in 2015 with a total number of 68 documents that is around 10 times the number of publications in the previous 14 years. The same level of activity continued until 2017, and then another sharp increase took place in the year 2018 when the number of publications reached 117 papers, which is a huge increase. Therefore, the level of publication is expected to continue growing although a slight decrease took place in 2020. In addition, Figure 2 demonstrates the type of documents published on this topic. The majority of documents published are article documents with a total of 288 papers followed by note documents with a total number of 108. However, in the last place came the short survey document with only 13 documents.
Data evaluation will be further conducted and consists of bibliometric analysis including citation, bibliographic coupling, and keyword co-occurrence analysis (Zupic & Čater, 2014;White & McCain, 1998;Small, 1999). Additionally, aside from the Scopus database, VOSviewer 1 software was also used for bibliometric analysis. Table 1 further discusses the key methodological terms used in this paper.
1 VOSviewer is a software application for designing maps based on network data and for visualizing and discovering these maps. A map can be generated based on a network that previously exists. VOSviewer is utilized to construct networks of scientific journals, scientific publications, scholars, research organizations, countries, and keywords. Elements in these networks can be linked by co-authorship, citation, co-occurrence, bibliographic coupling, or co-citation connections (van Eck & Waltman, 2014).

RESULTS
In this section, the bibliometric analysis results regarding medical insurance shall be reported.

Influential aspects of literature
In the following tables, we shall present the top 10 most influential literature as per country, authors, organizations, and the top 20 most influential articles.

Key journals distribution and network
The journal distribution network was identified using Scopus and VOSviewer software. The top 10 journals were ranked into two groups. The first ranking was based on the highest to lowest number of papers published on the topic, and then the second one was ranked from highest to lowest number of citations as shown in Table 2. As presented in Table 2, The Lancet was on the top 1 ranking in both sources by documents (99) and source by citation (3371). The Bulletin of the World Health Organization is also on the same rank, (rank 2) in both sources by documents (29) and source by citation (375). It was identified in the analysis that sustainable medical insurance was overlooked as there is no journal regarding this topic that was present in the top 10 rankings. The key journal distribution is also presented in Figure 3. The ranking was created by sorting the sources by documents and citations, from highest to lowest. It can be seen that The Lancet is the journal that contributed most to the topic. Using the Scopus and VOSviewer, the influential authors, their organization, institution affiliations, and countries of origin were identified. We ranked the authors, their organization, and countries of origin. We only presented the top 10 authors ranking, during the last 20 years, which was based on the number of citations, from highest to lowest.
Influential authors Based on Table 3, the most influential author by documents is Horton R. with 15 documents, followed by Nove A. with 7 documents, and Campbell J. with 6 documents. On the other hand, the authors with the most citations are Kruk M. E. with 851 citations, followed by Horton R. with 716 citations, and Soucat A. with 678 citations. Using the VOSviewer software, we have generated 2,189 authors; however, we only presented here the 10 most influential authors by documents and citations.
The 10 most influential authors by documents and authors by citations are presented in Figure 4. It was generated using the VOSviewer and Scopus.  Figure 4. Most influential authors generated using VOSviewer

Influential organization
As presented in Table 4 and Table 5, the World Health Organization (WHO) in Geneva, Switzerland has the greatest number of documents (13), followed by the London School of Hygiene and Tropical Medicine in London, the United Kingdom with 6 documents. This result represents that the WHO in Geneva, Switzerland has a strong focus on sustainable medical insurance. However, based on the highest number of citations Public Health Foundation of India came first with a total number of 797 citations revealing strong contributions to the field of study.  Using Scopus and VOSviewer, we have also generated the most influential organizations. We have selected the minimum number of papers to be 1 with at least 60 citations. The results have yielded 114 different organizations, which are presented in Figure 5 below.

Influential countries
The most influential countries by documents and citations were analyzed to gain deeper on where scholarly interest in medical insurance research has been located. The literature regarding medical insurance was authored in 51 different countries across the world, which means that there is a worldwide interest in this topic as shown in Figure 6 below.  Table 6, the United States (219) is the topmost influential country by documents, followed by the United Kingdom (145), Switzerland (90), and South Africa (57), which means that these countries have generated the most documents regarding the sustainable medical insurance. In addition to that, the country with the most citations is the United States (3787), followed by the United Kingdom (2801), Switzerland (2662), and India (1490). These four countries have the most citations in the field of medical insurance. The United States has the highest number of citations in the last 20 years, revealing that the country has explored, and studied most aspects involved in health insurance.

Key network analysis for research areas identification
With the help of the VOSviewer software, we have conducted a keyword network analysis to explore and research the various scope and administrations of sustainable medical insurance. As presented below, a network was presented based on the repetition of the keyword on sustainable medical insurance. The network shows the key concerns and main topics in the literature such as health insurance, health care quality, health service, sustainable development, public health, healthcare access, etc. It also presented that the global health, health care costs, and healthcare system barely occur on medical insurance. Researchers may have overlooked the health care cost, which is one of the crucial factors in designing pro-poor medical insurance.

Figure 7. Keyword analysis through bibliographic coupling using VOSviewer
Using Scopus and VOSviewer, we have also generated the top-ranked keywords. The keywords were ranked by their number of occurrences, from the highest to the lowest. Twenty (20) keywords were selected and presented in Table 7.

CLUSTER ANALYSIS
The cluster analysis is a tool used to categorize and group the same observations into several clusters (Sinharay, 2020). The grouping of the observations is based on the values of the various variables. The cluster analysis is the identification of the object's or observations' natural categorization (Boccard & Rudaz, 2013). In this paper, the cluster analysis for the literature on medical insurance is presented in Table 8. Various journals and articles focusing on the topic of medical insurance were clustered into health financing, maternal health, universal health coverage, health insurance, health workforce, global health, midwifery, and primary healthcare.  What is the significance of the expanded framework and projections for crosssectional evaluation of the health services packages? Table 8 represents the literature about medical insurance. The results were generated using the Scopus database and VOSviewer software, which provided us with 8 streams, with 10 journals in total. Through this analysis, we have identified various important journals that discuss different aspects of the medical insurance area (Nobanee, 2021). It provided us with more information about the subject matter, and gave us a crucial topic to conduct a further study within the future. This article provides an evaluation of the literature of works in the area of sustainable medical insurance. The study conducted in this area has been continuously increasing over the years and has contributed to the academic journals, which reflect the importance of medical insurance. With the ongoing issues that various countries, especially those countries with lower income, face regarding the lack of medical insurance, we expect that the government from these countries to develop the type of medical insurance suited for the less fortunate people.

FUTURE RESEARCH AGENDA
We have applied Bahoo, Alon, and Paltrinieri (2020) four-step method through bibliometrics and content analysis to determine the future research agenda. First, we have created a citation map by reviewing various articles related to medical insurance. From 638 article results, we have generated the top 10 most published articles during the last 20 years, from 2000 to 2020. Secondly, we examined all the influential articles, authors, countries, and organizations (Nobanee, Alhajjar, Abushairah, & Al Harbi, 2021). Then, to prevent bias results towards top citation, we have examined the outstanding articles. Finally, we have developed research questions by converting the future research agenda, which resulted in the four future research questions as shown in the above table. Our recommendation would be to develop and design a medical insurance that is pro-poor. Moreover, it is also recommended to provide high-quality medical services to establish a financially sustainable health system.

CONCLUSION
Many people across the world rely on medical insurance to have their medical expenses covered. However, not everyone can pay for their medical insurances, which has become a worldwide problem. Unfortunately, many people, especially in countries with lower incomes, suffer a lot as they are only relying on free health check-up, which does not cover serious illnesses. People who do not have medical insurance, and are financially challenged are only left one option, and that is to borrow money. However, loaning money makes them dig deeper into poverty. As a result, many of them just opted to let it be, and become worse. Thus, the study conducted a bibliometric analysis on the topic to pave the way for future researchers. The results revealed that the country that contributed most to the topic is the United States in both citations and documents level. In addition, the World Health organization was ranked first based on the number of documents published, however, Public Health Foundation of India was the first based on citations. Horton R. on the other hand was the first top author by the number of documents published and the second top author based on the citations. Finally, The Lancet journal was the top journal based on the number of citations and documents published in regards to the topic. Different streams were identified and further explained. Our results are unique and first of their kind as no other bibliometric analysis was conducted on the topic of medical insurance. Therefore, due to the analysis, we strongly recommend designing a medical insurance policy for the less fortunate people, which they do not have to pay for and can be used in any kind of illness. Meanwhile, like all other research papers, we have found a limitation in this study. The study used only the Scopus database as a source for various articles to perform the bibliometric analysis. Thus, to gain further information other databases could have been included to include data not available in Scopus.