Abstract
This research investigates recent trends and developments in the scope and impact of international collaboration in research publications. A number of prior studies in the field of Research & Development (R&D) have outlined the factors influencing an increasing internationalization in R&D. We transfer these findings in a complete sample of publication data from the years 2008–2015 in order to find out and describe how researchers in the two academic fields Health Care/Clinical Medicine and Business & Economics collaborate with foreign-based colleagues. We analyze how this research by international teams performs in terms of received citations, compared to their national counterparts. We find that international teams generally receive more citations than national ones. Furthermore, we outline how the number of countries with relevant publication numbers has grown and diversified over the last years, and author teams generally became larger and more international. In a last step, we show how emerging countries built up competence and knowledge over time, as an increase in received publication citations follows at a delayed pace to an increase in publication numbers. While there are some differences between the two academic fields Health Care/Clinical Medicine and Economics & Business, with, for example the former having approximately around ten times more publications per year, than the latter, the major structural trends and developments are similar in both fields, outlining the robustness of our analysis.
Keywords
Context and motivation
There are multiple reasons for scientific cooperation, whether it is to share resources, to leverage the specialization and knowledge of a particular institution, or to have a broader base for scientific exchange. The effect of cooperation on scientific publications, especially when it comes to international cooperation, as well as the impact of the number of countries or authors involved in a publication, is the focus of this publication. This publication therefore looks at the impact of collaborations on scientific publications and describes the effect of these publications on the perception of the publications over time. Through access to a local installation of Web of Science (WoS), this publication is based on a very large dataset covering the period from 2008 to 2015 for the scientific fields “Health Care/Clinical Medicine” and “Economics & Business”. Few scientists in the field of scientific research have access to such a dataset.
This paper addresses this research gap by conducting a long-term study of the impact of research collaboration and measuring that impact from different points of view. For this purpose, two fields were deliberately chosen that overlap as little as possible, one being a classic natural science subject (medicine) and at the core of the Web of Science database, and the other (eco) being more humanistic and with a much smaller coverage.
The research questions deal with the issue of whether the number of countries and authors involved as well as the status of a country as a developed or developing country for papers from different publication years can be used to draw conclusions about the perception of papers in the form of citations and whether this makes a significant difference.
The basis of the bibliometric evaluation of publications in clinical medicine and economics performed here, which has never been carried out before in this extent and with a focus on publication habits within the subjects, are the publications listed in the WoS. The “Science Citation Index” (SCI) introduced by Eugene Garfield in the 1950s, from which the WoS has developed over time, is the most widely used multidisciplinary publication and citation database in the scientific world.
Garfield’s central basic idea was to evaluate the selection of journals included in the database according to their importance for the respective subject area: from each subject area, the most relevant journals should be covered (core journals), measured by their impact. This selection procedure of the WoS, which is mainly based on the Journal Impact Factor (JIF), resulted in a database that is suitable for in-depth bibliometric analyses of many scientific disciplines. However, the version of the WoS on the Internet licensed by many scientific institutions is only of limited use for bibliometric analyses. Due to technical restrictions, the number of data sets that can be processed in one download process in the WoS is limited to 500. This number is clearly insufficient for a complete analysis of the fields of clinical medicine and economics.
In order to enable the German science system to carry out comprehensive and reliable bibliometric analyses, the Federal Ministry of Education and Research (BMBF) established the Competence Centre Bibliometrics in 2008, whose core task is to provide a data infrastructure for bibliometric analyses. The processing of publication data sets and the analyzability of all search fields is achieved on the basis of an Oracle database, which was set up especially for this purpose and is also known as a WoS local installation. In this database installation it is possible to query all fields of the WoS individually and in combination, to process the required amount of data records and to link them with own data tables.
“The structure schemes of the databases are designed and optimized with a view to their use for bibliometric investigations, i.e. in addition to the raw data supplied by the database producers, the bibliometric databases contain additional information and already precalculated indicators [1]”.
The data basis for this evaluation is the previously described local installation of the WoS by the Competence Centre for Bibliometrics. Under these conditions, the data source was selected to be the WoS with access via the local installation of the Competence Centre Bibliometrics. The competence center Bibliometrics provides the database Scopus in addition to the WoS. For the reasons explained above, especially the selection of core journals, the WoS was chosen. Even though the number of journals covered by Scopus is apparently much higher, the overlap of both databases on the document level is about 90%. This has not changed during the observation period chosen in this publication.
A classification system is used to determine the publications in the economic and medical subjects. The classification contained in the WoS is not suitable for this purpose due to the assignment of a journal to several subject areas. Therefore, the classification by Eric Archambault of Science Metrix is used, which is freely available on the internet. However, as it no longer leads to a completeness of at least 95% of the publications in each individual publication year for current publication years in this version, a supplemented version is used for this evaluation, which leads to sufficient coverage and completeness. For this purpose, journals that had previously not been considered were additionally included in the classification by means of a co-citation analysis and intellectual attribution, so that the coverage was increased accordingly.
The purpose of this paper is the following research question: What do the country affiliation of authors in research publications tell us about internationalization and collaboration trends in the last years on internationality and performance? The remainder of the paper is organized as following: in the upcoming second section, we expand on relevant literature in order to derive four hypotheses. In the third section we outline our methodology and explain how we analyze our sample from the HEALTH (short for short for “Health Care/Clinical Medicine”) and ECO (short for “Economics & Business”) field. The fourth section presents our empirical findings. Finally, in section five, we conclude with a discussion of our findings and give connecting points for future research.
Theoretical background and hypothesis
The composition of author nationality in academic research teams is a very under-researched topic, likely due to the challenges in acquiring meaningful data, and only a handful of research has generally addressed the author backgrounds of academic journal papers. Corsi, D’Ippoliti [2], for example, analyze the career developments of Italian economists by looking at their publication history and composition. Leydesdorff, Park [3], as well as Wagner and Leydesdorff [4] have analyzed academic co-authorship networks with a network analysis. Our analysis expands and updates these analyses by conducting a long-term study with an updated and unique data-set focusing on highly relevant academic fields, providing unique and recent insights.
In order to conduct a profound analysis, we use literature on Research and Development (R&D) internationalization, i.e. literature which looks at how firms conduct their R&D on an international scale. Both academic research and company R&D are driven by developing and applying new concepts; and research outlines the interlinkages between those two [5]. In the following we show relevant literature on R&D internationalization and how it can strengthen accordingly our hypotheses development and analysis of research team internationalization.
There are many reasons why citations are made, two of the most important being to acknowledge previous work or to identify methods and results of previous work that support one’s own thesis and findings [6]. This assumes that one knows these papers or can research them, so that they are preferably published in journals that have the highest visibility possible.
Visibility here means not only that the literature in question is published and accessible, but also that it is covered in appropriate literature databases such as Web of Science (WoS) or Scopus, making it findable. Furthermore, it must be perceived as relevant enough to be referenced [7]. Therefore, if China has fewer citations in earlier years, this can have different causes: Either there is a lack of high-quality work because China has yet to catch up in terms of scientific know-how, or there is simply a lack of visibility of the publications because it is still difficult for Chinese authors to publish as newcomers in journals that are dominated by the USA or UK as editors. In addition, the question which literature is perceived as relevant is, according to relevance theory, not only a question of content but also of writing style [8].
Team internationality and performance
The academic literature generally agrees that business and R&D internationalization is conducted in order to exploit market imperfections and existing competitive advantages [9–11]. This means by conducted R&D abroad and collaborating globally, firms have a broader access to local talent pools [12,13]. Talents, capacities and attitudes are not distributed evenly across the globe, but rather differ across environments and countries. The concept of “Lead Markets” in innovation, as defined by Beise [14] and based on the general concept developed by Bartlett and Ghoshal [15], explains how firms internationalize their R&D based on the respective local competencies, i.e. they have to source their knowledge where there is a wide availability of relevant input. This could be based in centers where there is particularly good funding, a specialization of universities and research centers, or a good access to data and markets [16]. With an increasing specialization and complexity of knowledge, the transfer and centralization of knowledge becomes increasingly expensive, favoring decentralized and local innovation activities [17–19]. A local embeddedness in networks, i.e. a proximity to local partners and innovation further fosters innovativeness and innovation performance [20]. On top, different local regulations might favor or hinder particular R&D activities [21–23].
Prior research, analyzing the team level of international R&D, has stressed the positive effects of internationalization through the variety in national or ethnic backgrounds [24–29]: With a diversity in backgrounds, the range of knowledge is wider and the teams have more experience with different environments [30,31]. The internationality strengthens knowledge spillovers [32,33]. Conducting R&D activities can be paralleled to conducting research: by collaborating with foreign researchers, we can likewise assume a higher range of knowledge and spillovers.
These arguments lead to the following hypothesis:
H1: International research teams have a higher number of citations in their publication.
International diversification
With the growth of China as a major economic power, the country’s R&D activities as measured by R&D expenditure and patent numbers have skyrocketed [34–37]. Big firms based in the Triad countries (USA, Western Europe and Japan) dominated R&D activities until recently and conducted R&D internationalization mostly across themselves [38].
Since the advent of the 21st century and the evolution of emerging countries, more countries have entered the stage and contribute now a relevant share of the world economy. Economic strength and research are connected, as the intellectual capabilities and funding increases [39–42]. We use these thoughts accordingly and assume to see a likewise development for academic publications.
We propose the following hypothesis:
H2: The number of countries with a relevant share of publications increases over the years.
Collaboration and specialization
Research is cumulative, i.e. builds upon each other, and complex [43]. With an increasing internationalization learning effects, experience and knowledge become relatively more important: knowledge leaders therefore can be expected to continuously innovate and specialize to keep their competitive advantage [44]. This strategy of specialization requires more inventors [22,45,46], so we can expect more authors per publication.
We propose the following hypothesis:
H3: The number of authors per publication increases over the years.
Competence build up
While upcoming nations, such as China, have significantly increased innovation activities, the initial level of activities was focused on a more basic level [47]. Analyses show the comparably inferior quality of Chinese patents, compared to economically more established nations, which implies that the competencies and quality first has to build up over time [48]. Such a catching-up process of quality to the quantity takes time [49,50]. Global networks of researchers have first to be built [51], in order to “enter the bubble”. We therefore expect that the visibility and somewhat quality of publications by upcoming nations follows the number of publications and propose the following hypothesis:
H4: The citations of publications develop at a delayed pace to the number of publications for upcoming nations.
Methodology
Data sample selection
The resilience of bibliometric analyses is strongly dependent on how well a subject is covered in the “Web of Science” (WoS). In order to estimate the coverage rates of scientific publications by subject, Heinze, Tunger [52] examined the cited references of the publications included in the WoS. The proportion of the cited references themselves contained in the WoS was examined. This method is also used by CWTS Leiden [53]. It is documented that the coverage rates in some subjects are not sufficient for a representative representation because in many subjects they are below 50%. Table 1 gives an overview of relevant scientific field and the rate of publications in that field covered by the WoS.
WoS rates of coverage (article, review, letter) by selected scientific field
WoS rates of coverage (article, review, letter) by selected scientific field
Source: Own illustration based on Heinze, Tunger [52].
For the selection of subjects in this publication, we have therefore based the coverage rates determined in Heinze, Tunger [52]. Against this background, we have deliberately chosen the two subjects “Clinical Medicine” and “Economics” for two reasons. First, Clinical medicine is one of the subjects with a very high coverage rate of around 90% and the topic is also one of the core subjects of the WoS. Economics, on the other hand, is only just over 50% and is also rather outside the core subjects of the database in terms of publication frequency. We have deliberately chosen this constellation in order to be able to use this combination of subjects, which are opposed in terms of coverage and publication frequency, to investigate similarities and differences in the characteristics and behavior of the bibliometric indicators. Second, both subjects are clearly defined and delimited against more niche or broader areas. Utilizing two distinct research areas helps to ascertain whether a determined effect can be generalized across scientific fields or whether it is distinct and explained by a subject’s peculiarities.
In 2008, the German Federal Ministry of Education and Research (BMBF) launched the Competence Centre for Bibliometrics (funding code: 01PQ17001) in order to allow the German academic system to carry out comprehensive and reliable bibliometric analyses. This center initially consisted of the former iFQ, the Fraunhofer Institute for Systems and Innovation Research (Fraunhofer-ISI), the Institute for Interdisciplinary Studies of Science at the University of Bielefeld (IISS) and the Leibniz Institute for Information Infrastructure (FIZ Karlsruhe) and was expanded by three further consortium partners in 2016: the Leibniz Institute for Social Sciences (GESIS), the Max Planck Digital Library (MPDL) and the Research Centre Jülich (FZJ). The core task of this center is to provide a data infrastructure which addresses the problems of data quality described above.
The processing of publication records as well as the capability to analyze all of the search fields is achieved on the basis of an Oracle database which was set up for this purpose and is also known as “local installation”. The tables in this database are normalized to each other according to the normal forms defined by Codd [54]. The objective is a redundancy-free form of data storage by splitting the data records into individual tables, as is generally the case with large amounts of data, in order to optimize running times and save memory. This means, for example, that information on journals can be found in a “Source” table, information on individual issues of journals in an “Issues” table, and the individual publication in an “Items” table. This data source is also enriched with adjusted address formats, i.e. the data are cleaned at the highest institutional level, using IDs.
The Competence Centre for Bibliometrics [1] refers to that as follows:
“The structural schemes of the databases are conceptualized and optimized for the purpose of bibliometric investigations, i.e. in addition to the raw data supplied by the database manufacturers, the bibliometric databases contain further information and precalculated indicators. Of particular added value in the data infrastructure operated by the Competence Centre for Bibliometrics is the institutional coding which has been implemented, i.e., the different notations of German institutions which are contained in the address fields of the databases are adjusted and merged, so that an unequivocal allocation of the publications to the institutions is supported”.
Under these conditions, the WoS was chosen as our data source, with access via the local installation of the Competence Centre for Bibliometrics. Although the center does not only provide the WoS but also the Scopus database, the WoS was chosen for the reasons mentioned above, especially in view of the selection of the core journals. The number of journals covered by Scopus appears to be significantly higher, however, the overlap between the two databases at the document level is approximately 90%. This overlap did not change substantially during the period under review in this publication [55,56].
A field classification was used in order to break down publications to their subject fields. The classification provided by the WoS (subject categories, SCs) is not suitable for this task. On the one hand, this is due to the heterogeneous nature of the subject categories, which means that certain categories are very disaggregated (e.g. medicine), while others, on the other hand, are presented in a far more aggregate form (e.g. physics). One of the major disadvantages of the WoS classification consists in that each journal can be assigned to up to five categories. This multiple assignment generates a considerable amount of redundancies, which makes the data less meaningful. For this reason, the choice fell on the classification provided by Archambault, Beauchesne and Caruso (2011), which assigns each journal to just one subject category and which, in terms of its degree of differentiation (with three hierarchical levels), has good differentiation (Heinze et al., 2019).
For each publication, it is also known in which country/countries the publishing institutions are located. For each country, the publication is counted only once, even if more than one institution originates from the same country. this means that a whole-count method is used and not fractionation. The same procedure is used for the citation counts, which are evaluated for the period up to 5 years after the publication year.
Based on this data basis, one data set each for economics and clinical medicine was created, which is the basis for further evaluations. This period was chosen because a longer-term development is to be investigated, with the emphasis on the characteristics and development of trends during this period. The fact that the last publication year considered is 2015 is due to the underlying citation indicator, which is measured over a period of 5 years from publication on top of time-lag in publication.
The data set contains data from different sources: The publication data as the most essential data come from the local installation of Web of Science of the bibliometrics competence center. This is where the references to the individual publications, to the authors, and to the countries in which the institutions are located are taken from. as well as to the citations. The classification of the publications into individual fields was mapped into the dataset using the ISSN. The same applies to data on open access status, which was taken from the Unpaywall [57] dataset and also matched via the ISSN of the journals. The journal impact factor was also matched into the dataset via the journal name. In this way, we created a unique dataset for an observation period of 8 years – the maximum amount of available years with full data availability.
Variables and measurement
We have merged relevant tables of the described bibliometric relational database and the “Science-Metrix” construct by Archambault, Beauchesne [58] and built variables, in order to carry out our analyses. We have constructed two databases with identical variables: one for publications in the field of medicine & health (short: HEALTH) and one in the field of economics & business (short: ECO).
We measure the visibility of each publication with the total number of citations received within the next five years after publication (TC5Y). The period of five years is widely accepted in the literature as a time-frame which is sufficiently long, as most citations a publication receives occur within these first five years [59]. As described above, this makes the last available year for analysis the year 2015. On top we have checked our results with the total number of citations received within the next seven years, in which we naturally limited our sample to 2013 as the last available publication year. These additional two years of received citations did not change the results in a significant way [59].
We measure author team internationality through the country lists of authors in each publication, in a matter comparable to international patent team analyses, as developed by Guellec and van Pottelsberghe de la Potterie [60] and expanded further by Gerybadze and Sommer [61], as well as Sommer and Bhandari [62] under the name “Host-Country Patenting”: we regard the single corresponding author in each publication as the initiator of the publication. If a corresponding author has more than one affiliation, only the current address is assigned to them in Web of Science (WoS). Therefore, each corresponding author is assigned exactly their single and main current address from the institution at which they are currently located. The country to which this institution belongs is considered the “initiating country”. If there is at least one author based in a country different to the country of the corresponding author, we consider the publication “international [63]”. If an author is assigned to several institutions belonging to different countries, the publication is assigned equally to all countries. In general, publications in this study are always counted in whole count and never fractionated, in order to specify the country-effects more clearly [62,64].
Publications are highly heterogeneous, in terms of citations received. In order to clearly identify effects, we classified journals with the journal impact factor (JIF), which puts the respective journal articles’ received citations of the last two years in relation to the number of articles. A higher JIF indicates that a journal’s articles, on average, have received more citations per article than a lower JIF. The JIF is a common index for a journal’s performance and visibility [65]. We conducted a robustness check for our analysis, double-checking our analysis for “Top Publications”, defined as the top 10% percentile of publications. The results do not substantially differ, i.e. the number of citations (TC5Y) we show in our analysis, is sufficiently precise.
We include the number of authors for each publication, as well as the number of total authors from the country of the corresponding author.
Empirical analysis and results
In order to give an overview over the datasets and trends of development, we first show the aggregated worldwide data per field, before breaking down the figures by country of corresponding author.
Global publication data
Tables 2 and 3 give an overview over the aggregated publication figures within the field of HEALTH and ECO respectively, as defined in the previous chapter. The publications are grouped into “All”, i.e. including all listed publications and its sub-set “International”, which means that the authors conduct research at scientific institutions in at least two countries. The Compound Annual Growth Rate (CAGR) shows the development across the full observation period between 2008 and 2015.
Publications overview HEALTH
Publications overview HEALTH
Note: CAGR calculated for 2015 to base year 2008.
Publications overview ECO
Note: CAGR calculated for 2015 to base year 2008.
The publication field of health is quite large and growing with over 290,000 publications in 2015, compared to 221,000 in 2008. Each of these publications receives, on average around 13 citations within the respective next five years. This rate has remained rather constant and even decreased slightly. The number of average citations per paper increased from 32 in 2008 to 35 in 2015. Considering the relative smaller CAGR for the number of received citations (ø TC5Y), this might be indicative that citations in HEALTH increasingly come from publications outside this scientific field.
Furthermore, we see an increase in average authors per publication from 5.5 in 2008 to 6.8 in 2015, as well as in increase in average number of author countries per publications. This already lends credibility to H2 and H3 for HEALTH. The detailed breakdown per country in the next part will scrutinize these figures further.
The share of international publications as a subset of all publications has increased to 22% in 2015, meaning that more than every fifth publication has an international co-author. These international publications substantially receive more citations on average, with an even increasing gap. On average, an international publication received more than seven citations more than the total average in 2015. This supports H1.
The field of ECO is substantially smaller than HEALTH, with less than 10% of its publication numbers. With a CAGR of over 7% the number of publications has grown quite dynamically to 27,000 in 2015. The received citations are also much lower, yet increased also with a CAGR of almost 4% to 9.6 received citations on average in 2015. However, in ECO papers cite more on average than in HEALTH and this figure increased rather strongly as well, to 47 citations on average in 2015.
The number of authors per paper is also substantially lower than in HEALTH, despite a similar upwards trend. On average 2.7 authors were listed per publication in 2015. H2 and H3 is therefore already supported for ECO as well.
The internationalization in ECO is, however, higher: first, the number of average countries per publication is higher than in HEALTH, and increasing, and second, the share of international to all publications is higher as well: in 2008 25% of all publications in ECO had at least one international co-author and in 2015 34%.
The number of average citations per international publication is also higher compared to the total average, thereby supporting H1 as well for ECO. However, this “internationalization-gain” is less pronounced, compared to HEALTH, with a lower gain, both absolutely and relatively.
Summarizing these findings, we already have support for the first three hypotheses: international publications receive more citations (H1), there is more international collaboration (H2) and the author teams become larger (H3). Generally, HEALTH has larger teams than ECO, which are slightly less internationalized. This is most likely attributable to the different procedures and characteristics of research publication in the respective fields, as outline in the theory chapter.
In the following we will scrutinize the publication data for selected countries, to gain further insights into the heterogenous patterns of research publication.
We focus on the countries with the most relevant data. We sort the countries of the corresponding authors into two groups and show the Top 5 for each group by publication number: one the one hand established countries with a growth rate of publication number (CAGR) below the world-wide average, shown in Tables 2 and 3, i.e. 3.92% for HEALTH and 7.32% for ECO and on the other hand upcoming countries, i.e. countries with a growth rate above the world-wide average. With this grouping we make sure to not just the “big players”, but also the particularly dynamic countries, i.e. the countries undergoing the biggest changes.
We can clearly see a shift from established to upcoming countries. In 2008 30% of all corresponding authors in HEALTH were based in the USA. That share has decreased to 25% in 2015, i.e. every fourth publication. In return upcoming countries, most notably China have almost tripled their world-wide share from 3.9% in 2008 to 11.5% in 2015, making that country the second largest country by number of publications, only behind the US. Japan and Germany, having ranked second in third, respectively in 2008 have clearly been overtaken by China with each accounting for approximately half of China’s publication numbers in 2015.
The general increase of the number of references, authors and involved author countries can be observed across every single country between 2008 and 2015, with substantial variations across countries. Japan, for example, stands out with relatively high author numbers and a low internationalization, i.e. a low average number of involved author countries. This matches with general observation on Japanese culture and international R&D collaboration [38,66,67]. Australia stands somewhat out in the group of upcoming countries, as it is the only country in this group not considered an emerging country [68] and where English is a native language. This potential ease in communication and publication might explain the comparably high internationalization rate.
With this breakdown we can clearly confirm Hypotheses 2 (more relevant countries) and 3 (more authors).
We can see for the upcoming countries that the strong growth in publication number is not matched by a comparable growth in average citations. In fact, for some countries such as Korea and Australia the number of the average received citations (TC5Y) even decreases, whereas for other countries it grows only slightly, if at all. This confirms Hypothesis 4: the citations of publications develop at a delayed pace to the number of publications for upcoming nations, as more publications do not immediately equate to more visibility.
The overall trends in ECO are somewhat comparable with certain differences: the USA are and remain the biggest nation in terms of publication number by corresponding author. This strong dominance has dropped from 40% share in 2008 to 29% in 2015. The UK, next to the US also a strong home for relevant academic journals ranks consistently second behind the US and lost only slightly in worldwide share between 2008 and 2015.
For the upcoming countries, we once again see China with significant increases in publication numbers and worldwide share, ranking worldwide third in 2015. As opposed to Health, it is not almost exclusive emerging countries which are “upcoming”. In fact, several European countries, including Germany, France and Spain are have significantly ramped up their publication numbers in the field of ECO.
Once again, we can observe growths in all fields, meaning between 2008 and 2015 not only the number of publications grew for all countries, but also the number of average citations received (TC5Y), the number of cited references, the number of authors and countries per publication.
As in HEALTH, the US are rather less internationalized with a comparably low number of involved countries per publication, whereas smaller and international countries such as the Netherlands show a comparably higher number. China stands out with a comparably higher number of authors per paper. This could be partially attributed to the culture and a more collectivistic approach to collaboration and partially to a strategy utilizing more diverse competencies of individuals and thereby increasing overall citations and visibility of the publication.
As we have seen already in the previous part, it becomes apparent that ECO is generally much smaller and much less interconnected than HEALTH, meaning not only the publication numbers are much lower, but also the number of citations and involved countries and individuals per publication.
Like with HEALTH, we can also confirm for ECO, Hypotheses 2 (more relevant countries) and 3 (more authors) with this breakdown.
For ECO the observation of Hypothesis 4 is less pronounced, yet visible: we see for the upcoming countries a stronger growth in publication numbers, than in received citations (TCJ5), indicating that visibility follows at a delayed pace. This gap is, however, significantly smaller than with HEALTH. It can be argued that a visibility and capability gap can be caught up more easily with ECO, than in HEALTH.
So far, we have looked in this part at all publications per corresponding author country. In the following Tables 6 and 7 we show respectively for HEALTH and ECO the subsample of international publications, i.e. all publications with at least one co-author who is working in a research institute in a foreign country. This helps us to investigate our Hypothesis 1 further, i.e. whether international research teams have a higher number of citations in their publication. The tables show the same countries as before and similar variables. We do not show the average number of involved countries as that number will be naturally higher per our definition of an “international” publication compared to the total. Instead of the worldwide share, we rather show in addition to the absolute number of the number of international publications per corresponding author country the share to all publication per corresponding author country. Naturally, that share highly correlates with the number of countries involved, i.e. a generally higher average number of author countries per publication corresponds to a higher share of international publications.
Two major findings can be derived: First, we can see strong upwards trends between 2008 and 2015, which is in line to the aggregate developments of all publications shown in Tables 4 and 5. Second, international publications are clearly more visible, i.e. receive more citations (TC5Y) and are more complex, as more references are used and more authors involved.
All publications HEALTH
All publications HEALTH
All publications ECO
International publications HEALTH
International publications ECO
The share of a corresponding author’s international publication is highly diverse across countries. In the UK, that share increased from 25% in 2008 to 35% in 2015, meaning that more than every third publication by a UK-based author in the field of HEALTH in 2015 had at least one foreign-based co-author. In the other side of the spectrum we have Japan with 9% and Turkey with 5% in 2015. In the case of the former that share has even slightly decreased from 2008, indicating that the number of non-international publications by Japanese corresponding authors grew at a higher rate. In the case of Turkey, we can also observe a much lower number of authors per international publication. A correlation between number of citations received (TC5Y) and number of authors becomes apparent, although it would be premature to deduce a clear causality from that.
Compared to all publications, international publications received significantly more citations in all years and for all countries, clearly confirming Hypothesis 1.
The findings for ECO are similar to that of HEALTH, just, as before, on a generally smaller stage: the publication numbers are lower, as well as the number of authors and received citations (TC5Y). As before, the number of cited references is mostly similar in 2008 and generally higher in 2015, meaning that ECO publications generally cite increasingly more publications, compared to HEALTH. The share of international publications is generally higher for all countries, compared to HEALTH. It can be argued that in the academic field of ECO, it is easier and more common to collaborate internationally in research, compared to HEALTH where locally bound physical equipment, e.g. laboratories, are much more common and required.
With generally lower publication numbers, the effect of one publication can be rather strong: an average citation count (TC5Y) for Taiwan of 4.0 in 2008 and 8.4 in 2015 has to be taken with a pinch of salt, considering the comparably low number of publications attributing to that citation count. It is interesting to see that the USA, the country clearly leading in terms of publication number is surpassed by the Netherlands in terms of citations received (TC5Y) for international publications.
Overall, we can clearly confirm Hypothesis 1 for ECO publications as well: international publication teams receive a higher number of citations.
Our findings provide novel insights for measuring and discussing internationality in a research setting. We contribute and expand on previous research in two ways: First, we combine research on bibliometrics with R&D internationalization and thereby connect two related concepts from their theoretical base. By connecting bibliometric descriptive data to their respective country and environment, a practical policy impact can be derived. Second, we utilize large scale and not widely available data, broken down to the respective author teams and utilize the whole count method for the co-authors of a paper [69]: Each country is credited once for a publication in which it is involved. This is independent of how many authors are assigned to institutions from that country. This approach gives unique insights into recent trends and developments.
We have analyzed publications in the field of Health Care, as well as Economics, two international and established fields of research. We have found that international research generally gets cited more, i.e. can be considered more visible and somewhat of a higher quality. We have shown how from a rather limit set of relevant countries, more countries have entered the stage and published in relevant numbers. The, still dominant, USA has strongly lost in worldwide share, compared to upcoming countries, such as China. For these upcoming countries we have shown a learning curve, meaning that an initial increase in publication numbers is followed by an increase in citations. Furthermore, we have shown the increasing complexity and connectiveness of research and researchers by outlining the increasing average number of researchers and involved countries per publication.
We have separated our analysis in two fields, namely Health and Economics. Health is a much larger field, with roughly ten times the publications than Economics in a given year. Differences in research, research communication and publication, as well as simply different numbers of researchers working in the field explain these differences and justify a separation of research analysis by academic field. The most relevant countries in terms of research in both fields differs to a degree across both fields. This shows that research competence is heterogeneously distributed across countries per academic field.
Current research still gives us little insights into the growing relevance of internationality in a research setting. Further analyses on this matter, with different indices and different foci can shed light on the increasing globalization in research teams which, in turn, can be of interest for policy makers.