Scientometric analysis of COVID-19 studies: how the velocity of science leads to discoveries and new technology Scientometric analysis of COVID-19 studies: how the velocity of science leads to discoveries and new technology

Scholars argue that the ‘‘science of science’’ studies have to investigate the critical role of exogenous events in the emergence of new research fields. The goal of this study is to analyze and explain the birth and growth of new research fields driven by exogenous event to science, such as COVID-19 (Coronavirus disease 2019) global pandemic crisis. This study here analyzes how the novel research field of COVID-19 emerges, in a comparative analysis with other scientific fields concerning respiratory illnesses (e.g., Chronic Obstructive Pulmonary Disease, COPD and Lung Cancer), to explain factors determining the unique dynamics of science that is generating scientific breakthroughs in a short period of time. The origin and evolution of the research field of COVID-19 reveal that has an acceleration of scientific production equal to a growth of 1.71% daily in 2020, laying the foundations for science advances and a likely paradigm shift in the treatment of infectious diseases with novel mRNA vaccines. Main results are generalized in properties that clarify the dynamics of science and explain the characteristics that generate the origin and evolution of new research fields driven by unforeseen crises with critical implications for technological and social change directed scientific progress of human societies.


INTRODUCTION
The evolution of scientific fields can explain the dynamics of science and technology associated with development of human society (Coccia, 2020(Coccia, , 2018Coccia and Watts, 2020;Gibbons et al., 1994;Haskins, 1965, Xu et al., 2021 1 . This study focuses on research field of Coronavirus Disease 2019  that is a new viral infection with a severe acute respiratory syndrome having clinical symptoms given by fever, dry cough, dyspnea, and pneumonia and may result in progressive respiratory failure and death (Coccia, 2020a(Coccia, , 2020c(Coccia, , 2020dCoccia, , 2021a. The COVID-19 crisis has raised challenges for economic, social and political order within and between states and a main question is how this scientific field of COVID-19 is evolving to generate new knowledge and innovative drugs to solve this global issue that threats nations and global economy (Guerrieri et al., 2020;del Rio-Chanona et al., 2020).
The first goal of this study is to analyze the evolution of the research field of COVID-19 compared to other vital scientific fields concerning respiratory disorders to explain the dynamics of science that is generating scientific breakthroughs in a short period of time. The second goal is to clarify the driving factors underlying the evolution of scientific field of COVID-19 and systematize findings in general properties that explain the evolution of science directed to scientific advances that support the development of human societies (cf., Coccia, 2019d). This study is part of a large body of research on the evolution of science that endeavors to explain how scientific disciplines emerge, evolve and decline in human society to clarify and forecast the structure and evolution in applied and basic sciences and design appropriate science and research policies (Coccia 2018(Coccia , 2020Bozeman 2016, Coccia andWang 2016). The vast literature on the dynamics of science has generated many contributions from different disciplines (Börner and Scharnhorst, 2009;Börner et al., 2011Börner et al., , 2012Scharnhorst et al., 2012;Kuhn, 1996;Price, 1986). However, the evolution of the research field of COVID-19 is hardly known, though it is showing unique characteristics in the history of science that deserve in-depth investigations. This is the first studies, to our knowledge, that endeavors to explain the characteristics of this new 1. Perception of the problem: an incomplete pattern in need of resolution is recognized 2. Setting stage: assimilation of data related to the problem 3. Act of insight: a mental act finds a solution to the problem 4. Critical revision: overall exploration and revision of the problem and improvements by means of new acts of insight According to some scholars, discoveries can be due to a collection of garbage cans in which problems and solutions are mixed randomly (cf., Newell and Simon, 1972, p.51; the garbage-can model by March and Simon in Cohen et al., 1972). In this context, discoveries are driven by scientists, institutions, nations, and other forces "knit, weave and knot" together (Latour,1987, p. 94) into an overarching scientific fabric (Latour, 1987;Latour and Woolgar, 1979;Callon, 1986). In particular, discoveries are driven by an activity of accumulation in science (Haskins, 1965;Whitley, 1984), application-driven, curiosity-driven and problem driven approaches (Coccia, 2012(Coccia, , 2012a(Coccia, , 2014a(Coccia, , 2016(Coccia, , 2016a(Coccia, , 2017(Coccia, , 2017a(Coccia, , 2017b(Coccia, , 2018aCoccia and Wang, 2015). The application-driven discovery is to find a solution to a problem in society, such as a new vaccine against epidemics that generate a high number of deaths (cf., Coccia, 2018b). Application-driven research is based on extrapolating the current established knowledge into new scientific and technological regimes, assessing pathways and risks. Kroeber (1917) considers two factors in the making of inventions: mental ability and cultural elements that must be brought together (cf., Coccia, 2019c. In fact, in the presence of a problem, its solution has to be socially desired to lead to discovery (cf., Bernal, 1939;Russel, 1952). In short, the need of an invention as problem solving activity has an association with factors of mental ability, cultural elements, and previous accumulation of knowledge (Coccia, 2014(Coccia, , 2014a(Coccia, , 2014b(Coccia, , 2015(Coccia, , 2015a. To put it differently, mental ability and cultural preparation are determinants in the origin of discovery in specific socioeconomic contexts to cope with consequential environmental threats or to take advantage of main opportunities (cf., Ogburn and Thomas, 1922;Coccia, 2015aCoccia, , 2017. Hence, the discovery may occur if there is a problem and a cultural need for solving it 4 | P a g e Coccia M. (2021) Scientometric analysis of COVID-19 studies: how the velocity of science leads to discoveries and new technology CNR --National Research Council of Italy (Coccia, 2015a(Coccia, , 2017. De Roeck (2016) argues that scientific discovery is possible thanks to funding of governments and funding agencies (cf., Coccia 2011Coccia , 2019Coccia , 2019a. Coccia (2018), investigating the evolution of scientific fields, suggests some empirical properties to explain dynamics of science and scientific advances: the first property states that the evolution of a research field is driven by few disciplines (3-5) that generate more than 80% of documents (concentration of scientific production); the second property states that the evolution of research fields is path-dependent of critical disciplines (they can be parent disciplines that have originated the research field or new disciplines emerged during the evolution of science); the third property states that the evolution of research fields can be also due to a new discipline originated from a process of specialization within applied or basic sciences and/or convergence between disciplines. Finally, the fourth property states that the evolution of specific research fields can be due to both applied and basic sciences. Other properties of the dynamics of science associated to scientific progress are (Coccia, 2020): (a) scientific fission, the evolution of scientific disciplines generates a process of division into two or more research fields that evolve as autonomous entities, creating new disciplines of scientific specialization; (b) ambidextrous drivers of science, the evolution of scientific disciplines by scientific fission is due to scientific discoveries or new technologies; (c) higher growth rates of the scientific production are in new research fields of a scientific discipline rather than old ones; (d) average duration of the growth phase of scientific production in research fields is about 80 years, almost the period of one generation of scholars.
In this research field, one of the problems is to clarify the endogenous processes driving the evolution of specific research field to cope with a crisis in society (Coccia, 2020g, h, i). This study confronts the problem just mentioned by developing an inductive analysis, which explains as far as possible dynamics, driving factors and underlying relationships of the evolution of COVID-19 studies to solve the global issue of COVID-19 pandemic and understand general properties that predict determinants of scientific discoveries to support scientific, technological, economic and social change in human development (Coccia, 2017c(Coccia, , 2017d(Coccia, , 2017e, 2018c(Coccia, , 2019(Coccia, , 2019aCoccia and Bellitto, 2018). Next section describes the methodology of this study.

Source and research setting
The study uses data of Scopus (2020), which is a multidisciplinary database that covers journal articles, conference proceedings, and books and allows citation analysis. Scopus database is used to detect scientific documents having in title, abstract or keyword the terms connected with lung diseases, such as: "COVID", "COPD", and "LUNG CANCER". Scientific products (articles, conference papers, conference reviews, book chapters, short surveys, letters, etc.) are a unit of analysis that allows to explain the structure and evolution of science leading to scientific discoveries.
A brief background of vital concepts under study is useful to clarify the methods of inquiry here.
First of all, COVID-19, as said, is coronavirus disease 2019 a novel viral infection that generates a severe acute respiratory syndrome with clinical symptoms given by fever, dry cough, dyspnea, and pneumonia and may result in progressive respiratory failure and death (Coccia, 2020a).
Chronic Obstructive Pulmonary Disease (COPD) is defined as a disease state characterized by the presence of airflow obstruction due to chronic bronchitis and emphysema. COPD is a highly prevalent disease affecting >10% of the population worldwide. The first manifestations occur at the cellular level with biochemical processes that lead to inflammation. Typically, the disease presents in the fourth or fifth decade with subtle symptoms, such as morning cough productive of mucoid sputum or simply an insidious progression of exertional dyspnea (Decramer and Cooper, 2010). COPD is thought to result from an accelerated decline in forced expiratory volume in 1 second (FEV1) over time (Lange et al., 2015). It is well known that COPD is a very common disease with great morbidity and mortality (Halbert et al., 2006;Siafakas et al., 2018).
Finally, lung cancer is a: "Cancer that forms in tissues of the lung, usually in the cells lining air passages" [as defined by the National Cancer Institute (2012)]. Lung cancer is one of the main diseases in several developed countries and a leading cause of cancer death worldwide (Coccia, 2012(Coccia, , 2012a(Coccia, , 2014b

Measures
Accumulation and development of knowledge in research fields under study here COPD and Lung Cancer) are measured with total document results given by: article, letter, review, note, editorial, conference paper, short survey, book chapter and conference review. In particular, data are gathered from Scopus (2020) in 2020 and 2021 (January) from April 2020 onwards, day per day for 260 days.
Documents of research fields under study per Subject area (e.g., Medicine, Biochemistry, Genetics and molecular biology, etc.) Document type of research fields under study (i.e., Article, letter, conference paper, book chapter, etc.) Documents of research fields under study per source title, which is given mainly by journals.
Documents of research fields under study per affiliation, which is given mainly by universities, public and private research labs, hospitals, etc.
Documents of research fields under study per funding sponsor, such as National Science Foundation, National Institutes, etc.
Documents of research fields under study per countries.

Data analysis and procedure
Data of documents (in short, Docs) per research fields (i = COVID-19, COPD and Lung Cancer) are gathered daily from 1 st April 2020 to 31 December 2020.
In addition, it is calculated the daily growth (%) of documents (Docs) per research field (i) given by: The data of documents and derived variables can be transformed in logarithmic scale to have a normal distribution for appropriate parametric statistical analyses or to design graphs and trends with comparable values. Secondly, the study analyzes the evolution of documents as a function of time.
The specification of the relationship is based on a linear model that fits scatter data: Y= scientific documents in the research field i (COVID-19, COPD, Lung Cancer) H0: σ1 2 -σ2 2 = 0 (the population variances of group 1 and 2 are equal) H1: σ1 2 -σ2 2 ≠ 0 ("he population variances of group 1 and 2 are not equal) If we reject the null hypothesis of Levene's Test, it suggests that the variances of the two groups are not equal; i.e., that the homogeneity of variances assumption is violated. If Levene's test indicates that the variances are equal across two groups (i.e., p-value large), Equal variances assumed. If Levene's test indicates that the variances are not equal across two groups (i.e., p-value small), the assumption is: Equal variances not assumed.
In particular, null hypothesis (H0) and alternative hypothesis (H1) of the Independent Samples t-Test are: H0: µ1 = µ2, the two population means are equal in groups H1: µ1 ≠ µ2, the two population means are not equal in groups.
The arithmetic mean of groups is compared considering pair of research fields as follows:      Table 2.
Parametric estimates of the relationship of scientific production in research fields as function of time (T=260 days) Note: *** p-value<0.001 a= predictor is a progressive series (N) indicating the time from 1 (1 st day), 2 (2 nd day) … to 260 (260 th day) from April to December 2020.   Finally, the Independent Samples t-Test compares the means of two independent groups in order to determine whether there is statistical evidence that the associated population means of ∆Docs are significantly different.  In order to assess the significance of the difference of arithmetic mean of ∆Docs between groups under study (  Table 4 shows main results about a statistically significant difference of arithmetic mean of ∆Docs between groups. In particular, table 4 substantiates that: • There was a significant difference in mean ∆ (%) between research fields of COVID-19 and COPD (t264.809 = 4.69, p < .001).
• Whereas, arithmetic mean of ∆ (%) between research fields of COPD and Lung cancer is not different but is rather similar (t505.496 = .161 p < .872).
The conclusion of these statistical analyses are that the rate of evolutionary growth of the research field of COVID-19 is definitely statistically different from other normal research fields, such as COPD and Lung cancer, having an accelerated and disproportionate growth with the potential to lead to scientific breakthroughs in a short period of time (cf. figure 1).

DISCUSSION
The accelerated growth of the research field of COVID-19 is due to some driving forces that are described as follows.

 Driving areas of research in COVID-19 studies
The most productive research areas in the study of COVID-19 are mainly related to life science (Figure 3). Of the top 10 research areas about 58% of documents published on COVID-19 is in Medicine, 9.3% in Social science and 8.5% in Biochemistry, genetics and molecular biology. In the top ten areas, there is also environmental science (3.5%) because manifold studies analyze possible relations between air pollution and the spread of COVID-19 (Coccia, 2020) 2 . This research field of COVID-19 confirms the properties by Coccia (2018) 2 Cf., Coccia, 2014c. 13 | P a g e Coccia M. (2021) Scientometric analysis of COVID-19 studies: how the velocity of science leads to discoveries and new technology CNR --National Research Council of Italy that the evolution of a research field is driven by few disciplines (3-5) that generate more than 80% of documents (concentration of scientific production).  Table 5 shows the top ten journals that have published more contributions on COVID-19 at 31 December 2020. Five of the top ten journals are related to medicine, virology, public health and one is interdisciplinary with a percentage higher than 10% each on a total of the top ten. In the top ten, there are also journals related to environmental and sustainability science for the reasons associated with relations between air pollution and the spread of COVID-19. In the top ten, it is also important to note the presence of the journal "Medical Hypothesis" because in the presence of a new and little explored problem in society, alike COVID-19, a lot of scholars have suggested at beginning multiple working hypotheses to explain likely determinants of transmission dynamics and treatments to reduce the impact of COVID-19 pandemic in society.  China, 2 in England, 2 in Italy, 1 in France and 1 in Canada (Table 6). The top ten funding organizations that have supported the publication of documents on COVID-19 are in USA (4 funding sponsors), China (2), UK (2) and Brazil (2). In particular, institutions in the USA have funded about 43% of published documents of top ten institutions, in China about 35%, in UK roughly 12.5% of documents and finally in Brazil about 9%. Table 7 shows the driving role of funding organizations in two large countries given by the USA and China that have funded more than 78% of documents on COVID studies among top ten instructions. De Roeck (2016) argues that scientific discovery is due to main role of funding of governments and funding agencies. The highest production of COVID-19 studies is concentrated in 4 countries that have published about 68% of documents of the top ten countries (Table 8). This result further confirms the concentration of scientific production in specific geoeconomic contexts (Coccia, 2018). These results can be also due to main socioeconomic factors as explained by Coccia (2020): 16 | P a g e Coccia M. (2021) Scientometric analysis of COVID-19 studies: how the velocity of science leads to discoveries and new technology CNR --National Research Council of Italy  Science advances and new technology are a source of socioeconomic power for countries to take advantage of important opportunities or to cope with consequential environmental threats.
 Science advances and new technology are drivers of economic and productivity growth for nations and of a higher wellbeing of citizens.
 Science advances and new technology increase reputation and recognition of nations worldwide to support an endogenous power in international system based on scientific and technological superiority that endorses their leadership and affects other geoeconomic regions to take advantage of commercial and political opportunities.

PROPOSED PROPERTIES OF THE EVOLUTION OF RESEARCH FIELDS, CRISIS-DRIVEN
The inductive analysis here, based on case study of the research field of COVID-19, has main theoretical implications to explain the evolution of research fields that generates scientific discoveries that can be systematized with following empirical properties of the dynamics of science. 1.
The first property states that the evolution of a research field is driven by average daily growth of 17 | P a g e Coccia M. (2021) Scientometric analysis of COVID-19 studies: how the velocity of science leads to discoveries and new technology CNR --National Research Council of Italy scientific production over one year of about 0.50% that generates scientific breakthroughs in the long run.

2.
The second property states that the evolution of research field with high rate of average daily growth over one year of more than 1.5% generates scientific breakthroughs and scientific and technological paradigms shifts in a short run.

3.
The third property suggests that a high rate of average daily growth over one year of more than 1.5% are driven by consequential environmental threats for human societies, such as COVID-19 pandemic crisis.

4.
The fourth properties states that the emergence of a new research field can be due to consequential environmental threats and relevant problem in human society, such as COVID-19 pandemic caused by a novel coronavirus called SARS-CoV-2, a problem that has not been seen before.
The main findings of this study suggest that in general research fields evolve with accumulation of "normal science" that have discontinuous transformation in the long run by new theoretical and empirical approaches that support the transition from an existing scientific paradigm to an emerging one (Kuhn, 1996). In the study of the social dynamics of science, Sun et al. (2013) argue that new scientific fields emerge from splitting based on branching mechanisms, such as specialization and merging of social communities that can capture the synthesis of new fields from old ones. However, what this study adds is that in the presence of consequential environmental threats and relevant problems for human society (such as novel coronavirus called SARS-CoV-2 that has generated COVID-19 and a lot of deaths in society), new research fields can emerge as specialties 3 and evolve with accelerated rates of growth that generate radical transformation and discoveries in a very short period of time to solve and/or reduce the emergency. In fact, the COVID-19 pandemic crisis has generated in medicine the specialty of COVID-19 with an accelerated rate of growth that has supported a scientific paradigm shift Coccia M. (2021) Scientometric analysis of COVID-19 studies: how the velocity of science leads to discoveries and new technology CNR --National Research Council of Italy towards a novel type of vaccine based on messenger RNA, known as mRNA for high levels of protection by preventing COVID-19 among people that are vaccinated. This new approach is different from the classical approach to vaccination that is based on two categories of vaccines, live-attenuated and killed, such as vaccines for polio and measles, mumps and rubella (MMR), etc. The scientific breakthrough of mRNA vaccines is based on accumulated knowledge that the infective process itself is effective in raising an immune response and genetic engineering can be utilized to construct virus-like particles from the capsid and envelope proteins of viruses (Smoot, 2020). In fact, immunogenic proteins of a pathogen can be engineered into a non-pathogenic or attenuated vector (e.g., adenovirus, Salmonella) that can stimulate the immune system similarly to a real infection. Currently, antigens have been shown to be deliverable as nucleic acid (either RNA or DNA) for the host to translate the encoded protein(s) for processing by the immune system (Smoot, 2020). COVID-19 has accelerated the transition towards these types of vaccines based on new approaches and leading companies in pharmaceutical sector, such as AstraZeneca, Pfizer, etc. are now focusing human and economic resources on vectored, subunit, RNA, and DNA platforms, respectively. The messenger RNA (mRNA) vaccines can leapfrog the barriers of developing traditional vaccines, such as producing noninfectious viruses, or producing viral proteins at medically demanding levels of purity. Moreover, mRNA vaccines eliminate a lot of the manufacturing process because rather than having viral proteins injected, the human body uses the instructions to manufacture viral proteins itself. Also, mRNA molecules are simpler than proteins. In short, for vaccines, mRNA is manufactured by chemical rather than biological synthesis, so it is much faster than conventional vaccines to be redesigned, scaled up and mass-produced. mRNA vaccines are being tested for other viral agents, such as Ebola, Zika virus, and influenza (Komaroff, 2020 Overall, then, the scientific background of mRNA has been accelerated in the presence of unpredictable COVID-19 pandemic crisis (Abbasi, 2020;Heaton, 2020;Jeyanathan et al., 2020;Komaroff, 2020). In fact, in the presence of COVID-19 pandemic that threats public health of nations from 2020, the paradigm shift of mRNA vaccine is driven by manifold factors, such as: accumulation of knowledge in understanding the structure of DNA and mRNA, process to produce a protein, the invention of a new technology to determine the genetic sequence of a virus, process to construct an mRNA that would make a particular protein, solution of problems associated with mRNA to be injected into the muscle of a person's arm from finding its way to immune system cells deep within the body, and coaxing those cells to make the critical protein, and finally the support of governments and cultural need to apply this new technology in the presence of a environmental threat given by COVID-19 global pandemic crisis (Coccia, 2015a. (1986) suggests that the main factor that leads to the creation of a new specialty is the demand to make effective research possible. The success in solving relevant problems can generate discoveries that support the scientific development to deal with consequential problems for further research (cf., Mulkay, 1975). In addition, socio-economic-political and cultural needs can drive the development of new technology and support the search for new approaches (Coccia, 2014(Coccia, , 2014a(Coccia, , 2015aGood 2000, p. 271). The evolution of science is a natural process that is due to a cumulative change driven by ideas during the exploration and solution of new and consequential problems in nature and society that fuel scientific discoveries (cf., Coccia, 2016Coccia, , 2016a2017;Scharnhorst et al., 2012;Popper, 1959). In general, discoveries and new ideas can be explained with the necessity of solving a problem that is a main driving force that induces a series of scientific advances (cf., Iacopini et al., 2018;Ogburn and Thomas, 1922;Tria et al., 2014). In this context, literature shows that factors determining the emergence and evolution of research fields are due to splitting and merging of social communities: splitting can account for branching mechanisms, such as specialization and fragmentation, while merging can capture the synthesis of new fields from old ones. The birth and evolution of disciplines is thus guided mainly by the social interactions among scientists (Sun et al., 2020). This study revels interesting results of the emergence and evolution of research fields, investigating the new specialties of COVID-19. In particular, relevant problems and environmental threat generated by unpredictable crisis to prevent can support scientific advances with accelerated production of new studies directed to explain and solve unknown problems generating discoveries and also scientific paradigm shifts in the presence of social and cultural conditions given by willingness of institution and society to invest in new scientific research to solve problems in human society (cf., Becsei-Kilborn, 2010).

Price
However, a limitation is that sources of this study may be incomplete, or only capture certain aspects of the ongoing dynamics of science in this new field of research; hence, conclusions here are of course tentative because we know that other things are not equal in the dynamics of science over time and space. There is need for much more research into the relations underlying the evolution of scientific fields in the presence of crisis and environmental threats. Overall, then, the study here cannot be enough to explain the comprehensive characteristics of the evolution of science within and between research fields in the presence of unforeseen shock and crisis in society, because scientific fields and society change rapidly within very short periods of time under a general social stress. Therefore, to conclude, the identification of general patterns of science in the presence of social, economic and health crisis is a non-trivial exercise. The future development of this study has to reinforce proposed results here with additional empirical research considering other new emerging research fields both in the presence of stable and unstable evolution of society.
Declaration of competing interest. The author declares that he has no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. No funding was received for this study.