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Publicly available datasets were analyzed in this study. This data can be found at: Scopus Google Scholar Web of Science.
Obamacare is the colloquial name given to the Affordable Care Act (ACA) signed into law by President Obama in the USA, which ultimately aims to provide universal access to health care services for US citizens. The aim of this paper is to provide an overview of the political-legal, economic, social, management (or administrative), and medical (or health) repercussions of this law, using a bibliometric methodology as a basis. In addition, the main contributors to research on ACA issues have been identified in terms of authors, organizations, journals, and countries. The downward trend in scientific production on this law has been noted, and it has been concluded that a balance has not yet been reached between the coexistence of private and public health care that guarantees broad social coverage without economic or other types of barriers. The law requires political consensus to be implemented in a definitive and global manner for the whole of the United States.
Keywords: Obamacare, Affordable Care Act, strategic diagram, PEST analysis, SciMATThe Affordable Care Act (ACA) signed into law by President Obama in the USA, often referred to as Obamacare, aims to provide universal access to healthcare services for US citizens. At the time of its enactment in 2010, the vast majority of the health care system was privately owned and there were 48 million uninsured non-elderly persons (1).
Previously, several initiatives had been made, including the Social Security Act of 1935, enacted by Franklin D. Roosevelt. This law established a pension system for those over 65 years of age, although in the following years it also covered the family members of workers who died prematurely, and the disabled (2). It is also worth mentioning the reform signed into law by Lyndon B. Johnson in 1965, which consisted of the creation of the two major public health services in the USA: Medicare and Medicaid. These programs were created in order to provide coverage to people with fewer resources and those who were in a state of social vulnerability. Specifically, Medicare was designed essentially for people over 65 years of age, although it also included certain vulnerable populations, which mainly covered people with limited resources (3).
From its conception to the present day, the ACA has sparked a great debate in society, obviously mainly in the USA, but also in other countries. It is undeniable that this debate is often influenced by certain interest groups that promote it, since they may have political, economic, or other interests. This study aims, as far as possible, to give an objective view of the ACA. For this reason, high-quality scientific publications will be used as a basis for the study. However, there is a large number of such publications available on this subject. In order to achieve the greatest possible objectivity given such a large amount of information, in this study we have opted to use bibliometric techniques. Although the concept of bibliometrics itself can be understood differently (4), there is a certain consensus in defining it as the use of quantitative techniques (mathematics and statistics) on the documents published on a certain subject. Thus, one advantage of bibliometric indicators is that they make it possible to measure not only the purely quantitative aspects of the subject under investigation but also its qualitative nature (5). The success of this study will be largely based on the prior documentation of the area to be investigated, since without such an understanding of the area it would be impossible to interpret the results obtained by the bibliometric analysis, which, furthermore, requires considerable refinement and a qualitative evaluation in order to obtain the definitive results.
The main objective of this study is, therefore, to provide a cross-sectional view of the implications of the ACA from its enactment in March 2010 to the present day, by comparing how it may have progressed during this period. The PEST analysis (political, economic, social, and technological) is useful for outlining the strategic environment of a region or subject matter (6). By adapting this type of analysis, this paper aims to study the political (also including related legal aspects), economic, social, management (or administrative) and medical (concerning health) aspects related to the implementation of the law, therefore, it aims to make a PESMM analysis of Obamacare. All of which in accordance with the perspective of the various high-quality scientific publications that have been published on ACA. Evidence of this type of PEST analysis using bibliographic sources is available here (6). The secondary aims of this paper fall within those typical of bibliometric analyses. As such, we also want to identify the main researchers interested in ACA in terms of countries, organizations, journals, and authors.
The rest of this paper is structured as follows. In Section Related work, a study of related research has been carried out, since other authors have conducted cross-sectional studies on the ACA, highlighting the differences between them and our proposal. Section Research methodology presents the research methodology followed. Section ACA analysis from a bibliometric perspective presents and analyzes the results of the application of this methodology in order to achieve the proposed objectives. Finally, conclusions and proposed future work are discussed.
A search for systematic literature review (LR) or bibliometric studies (BS) related to the ACA was carried out, obtaining a current overview of these papers by restricting the search to papers published from 2020 onwards, using both Clarivate and Google Scholar. After performing the corresponding searches and studying the results obtained, the related papers have been summarized in Table 1 .
| References | Description | Type |
|---|---|---|
| Xu et al. (7) | Impact of ACA on colorectal cancer outcomes. | LR |
| Matkin and Ring (8) | Impact of the ACA on academic medical centers. | LR |
| Song et al. (9) | Impact of the ACA on dental health | LR |
| Chernew et al. (10) | The evolution of the ACA in payment systems | LR |
| Lee et al. (11) | Impact on women's coverage, utilization, affordability, and health after the ACA: A review of the literature. | LR |
| Zhao et al. (12) | Analysis of access to care across the cancer control continuum in the ACA over the past decade. | LR |
| Neiman et al. (13) | Impact of ACA on surgical patients. | LR |
| Glied et al. (14) | Study of the financial barriers of the ACA | LR |
| Peikes et al. (15) | Effects of the ACA on primary health care | LR |
| Ercia et al. (16) | Analysis of ACA in patient enrollment strategies | LR |
| Norris et al. (17) | Impact of ACA on the utilization of cost-sharing elimination of preventive care services. | LR |
| Soni et al. (18) | How ACA insurance expansion has affected health outcomes. | LR |
| Kamstra et al. (19) | Analysis of how the ACA fell short for a vulnerable population in Hawaii | LR |
| Kates et al. (20) | ACA coverage of HIV treatment and prevention funding in the USA. | LR |
| Nathan et al. (21) | Evaluation of the benefits of the expansion of Medicaid for oncology patients. | LR |
| Moss et al. (22) | Analysis of cancer care with the ACA Medicaid expansion. | LR |
| Hilts et al. (23) | Impact of hospital partnerships on population health. | LR |
| Fiedler (24) | Legislative history of the ACA | LR |
| Buntin and Graves (25) | Study of the evolution of health care spending since the approval of the ACA. | LR |
| Corlette et al. (26) | The effect of the ACA on the individual insurance market | LR |
| Adigun et al. (27) | Impact of the ACA on the health care of immigrants in the United States | LR |
| Rozier (28) | Community benefit assessment of not-for-profit hospitals in the U.S. | LR |
| Himmelstein and Woolhandler (29) | Analysis of medical care with the ACA | LR |
| Bossick et al. (30) | Impact of state legislation on reproductive health in the United States. | LR |
| Layton et al. (31) | Impact of ACA on long-term care. | LR |
| Lindley et al. (32) | Analysis of children's palliative care in the United States since 2010. | LR |
| Minas et al. (33) | Analysis of health disparities in oncology treatment in the ACA. | LR |
| Morgan et al. (34) | Study of preventing readmissions due to trauma in ICUs | LR |
| Marye (35) | Study of the relationship between insurance type and emergency department use for children with asthma in the United States during the ACA. | LR |
| Titus and Kataoka-Yahiro (36) | Analysis of barriers to health care access in Hispanics with type 2 diabetes in the ACA. | LR |
| Watkins et al. (37) | Analysis of the customized preventive services of the ACA | LR |
| Zavala et al. (38) | ACA disparities in cancer health in ethnic minorities. | LR |
| Hong et al. (39) | Impact of the hospital value-based purchasing program on Medicare. | LR |
| Clark et al. (40) | Analysis of the prevalence of health insurance among gender minorities. | LR |
| Steinberg et al. (41) | Racial differences in outcomes after receiving advanced heart failure therapies in the ACA | LR |
| Manchikanti et al. (42) | Comparative analysis before and after 2009 in patients undergoing vertebral augmentation treatment with Medicare. | LR |
| Ermer et al. (43) | Impact of Medicaid expansion for cancer care. | LR |
| Current work | Impact of the ACA at a cross-sectional level: political-legal, social, economic, medical and management. | BS |
As can be seen, there are several review papers related to the ACA, but many of them are specific to certain aspects of the law, and those that are more general are not analyzed using bibliometric techniques. Based on the searches carried out, we can conclude that this paper is original and that nothing similar exists in the literature.
In this section we will explain the research methodology followed in this study and the results of which will be shown in the following section.
Bibliometric mapping is an important field within bibliometrics. Its objective is to show the structural and dynamic aspects of scientific research to enable further interpretation. In this paper we will follow the methodology shown in Figure 1 , which is inspired by Cobo (44) and Galán et al. (45). The advantage of this methodology is that there are tools that allow us to carry out most of its stages, and in this study we mainly use the following tools: SciMAT (5), VOSviewer (46), and Microsoft Excel.
Steps used in the research methodology.
Each stage is described in more detail below.
This study aims to achieve the following specific objectives: to extract and analyze the different issues that have been involved in different aspects of the ACA: political, social, health, economic and management or administration, to further study the political and social aspects involved in the ACA, to study how these issues have evolved from the period of implementation of the ACA to the present-day, to identify the main researchers interested in the ACA in terms of countries, organizations, journals and authors, and to study the trend of scientific production concerning the ACA.
To carry out this study we required high-quality scientific literature published on the ACA. There are several bibliographic database options (45): Clarivate, Scopus, Google Scholar, etc.
In this paper, we have used Clarivate as many authors consider it to be a higher quality source, although there are fewer papers available. This is not a problem in this case, as a preliminary study has identified several thousand articles on ACA.
The time period chosen for the study will be up to 2021, not including the current year, 2022, in order for the work to be reproducible. Specifically, the chosen dates are 01/01/2008 to 12/31/2021.
In the Clarivate advanced query option, the following expression has been used on the Clarivate Web of Science Core Collection:
TS = (“obamacare” or “obama-care” or “obama care” or “Affordable Care Act”)
The TS field implies searching for publications on ACA (including different forms of spelling and informal terms) in the title, abstract and/or keywords. The query was carried out in April 2022, obtaining a total of 6,369 documents.
The documents obtained were exported from Clarivate to seven files since only up to 1,000 documents can be exported at a time. Once this was done, they were included in SciMAT since this tool has several functionalities for data preprocessing. To increase the quality of the data, the keywords have been normalized by merging them in their plural and singular forms, words have also been merged with their corresponding synonyms, and several keywords that refer to the same concept have been identified by using the Levenshtein distance in SciMAT.
To obtain an overall view of the subject under analysis, we are going to perform the analysis from different points of view or dimensions. Table 2 explains each of these dimensions and includes the types of quantitative analysis we are going to perform on them, which are typical of the tools we are using in this paper (SciMAT and VOSviewer).
Dimensions of analysis, meaning, and type of analysis available for them.
| Dimension | Description | Type of analysis |
|---|---|---|
| Sources | Journals, conference proceedings… | Citations |
| Authors | Author and co-authors | Co-authorships |
| Organizations | Authors' affiliations and funding organizations | Co-authorships |
| Countries | Authors' countries | Co-authorships |
| Topics | Keywords | Co-occurrences |
According to the type of analysis, we use the following bibliographic relationships that will allow us to quantitatively relate various bibliographic elements, thus allowing us to construct the corresponding networks (45); co-authorship, the relationship of the articles is determined according to the number of co-authorships; citation, the relationship of the articles is determined according to the number of times they cite each other; co-occurrence, the relationship of keywords is determined according to the number of documents in which they appear together. For this purpose, the equivalence index is often used.
After this construction, a process of segmentation or grouping of the elements that are considered similar is usually performed. Therefore, nodes that are considered to be close enough to each other and sufficiently separated from the other groups are grouped together. An example of a thematic network can be seen in Figure 2 .
Thematic network where the different elements (dimensions) and segmentation of the network are linked using a different color for groups, group (A) and group (B).
This type of diagram is particularly interesting in the analysis of co-occurrences as it allows the importance of each of the topics that have emerged in the analysis to be outlined. It is based on two measures (5):
Centrality measures the degree of interaction of a network with other networks. This value can be understood as a measure of the importance of an element in the development of the entire analyzed field of research.
Density is the internal strength of the network or element in question. This value can be considered to be a measure of the degree of the development of the topic.
The strategic diagram makes it possible to classify the topics that were identified in the bibliometric study into four categories, as shown in Figure 3 .
Strategic diagram (A), examples of an evolution diagram (B), and overlap diagram (C).
The topic divisions have been divided by periods, and afterwards, the evolution and overlap diagram of the corresponding items is obtained, which shows the evolution of the topics and the overlapping of these detected topics (which is an indicator of their stability) in successive periods of time. An example of both diagrams is shown below in Figure 3 .
Based on the results obtained for each dimension, mainly the graphs already mentioned in the previous points, the researcher must interpret and, in many cases, fine-tune the results based on the selection of the various parameters that the tools have, until they understand what is happening in that particular analysis.
Although this methodology is largely based on quantitative techniques, the researcher, based on the different global results obtained for each dimension (subject, authors, countries, etc.), has to interpret them globally and try to meet the objectives set out in the first stage.
In this section we will explain the results of applying the previously mentioned research methodology to the topic analysis. To do so, we will begin by analyzing the different topics related to the ACA that were identified in the bibliometric analysis and we will try to look at them from the different PESMM perspectives mentioned above. In this analysis, an analysis of the temporal evolution of these issues must be carried out, since the application of the law has evolved with the different changes of government, judicial resolutions, etc. Subsequently, we will analyze the different sources (journals, conference proceedings, etc.) where we have found studies related to the ACA. We will then analyze the contributions made to this area by the most important authors, countries and organizations. Finally, we will extract the overall results of the analysis and extract the fundamental factors of the intended PESMM analysis.
As mentioned above, this type of analysis is essential in order to meet the main objectives of this study. As such, we will analyze the keywords of the articles obtained in three different ways: those specified by the authors themselves; those specified by the Clarivate for each article; and the additional keywords extracted from the title of the article and the abstract. It is important to remember that for this type of analysis we will use the co-occurrences of these keywords among the different articles, as mentioned in Section Research methodology. In other words, one keyword will be related to another according to the number of documents in which both appear together.
We will divide the period of analysis in two, since the ACA itself has undergone several variations from its conception to its attempted implementation, motivated among other factors by the complexity of the implementation itself, judicial vicissitudes… but above all, one such determining factor has been the different changes in the U.S. governments:
Until 2017: would be the stage of growth in scientific interest in this subject, including work prior to the law itself and the implementation period under the Obama administration. Obviously, this administration has been a great promoter of this law, so its development during this period is quite noticeable.
2017–2022: is the post-Obama stage, which included that of President Trump and later Biden. This stage was also influenced by the pandemic caused by Covid-19. The political changes after the 2016 elections brought about reforms to the law that generated uncertainty, although after Biden's arrival to power the law now seems to be more entrenched.
For the analyses shown below, the SciMAT tool will be used primarily for the construction of the strategic and evolution/overlap diagrams (explained in Section Research methodology). Note that prior to the construction of these diagrams, the keywords have been preprocessed by grouping synonymous terms (although written differently) as explained in Section Data pre-processing.
Figure 4 shows the strategic diagram for the first analysis period “until 2017.” This diagram was initially constructed with SciMAT and was enhanced with the typology of each quadrant in order to determine the importance of the topics. In addition, each of the topics has been qualitatively typified into five major areas or topic categories, each of which is related to the ACA:
