Evaluation of The Psychiatric Research Output From Turkey Via Web Of Science Database: A Bibliometric Analysis
Zehra Topala, Ilhan Bahsib, Ali Evren Tufanc
a Department of Child and Adolescent Psychiatry, Gaziantep University, Gaziantep;
b Department of Anatomy, Faculty of Medicine, Gaziantep University, Gaziantep;
c Department of Child and Adolescent Psychiatry, Abant Izzet Baysal University, Bolu, Turkey
Background: Global scientific research output is continuously accelerating. Although psychiatric scientific output is increasing, factors such as health systems, scientific programs and financial supports that vary between countries lead to varied levels of contribution. This cross sectional bibliometric study aims to analysis the articles bibliometrically which conducted by researchers from Turkey and indexed in SCI-E index of the Web of Science (WoS)database in the category of Psychiatry.
Methods: According to 2019 data, in the WoS database, journals in the Psychiatry category and indexed in the SCI-E were determined. Publications from Turkey that were published in these journals was determined. For each publication, all information relevant to the analysis was exported to Microsoft Excel and EndNote Desktop. Also, VOSviewer software was used to create a collaboration and word co-occurrence network.
Results: There were 5293 publications which have at least one author from Turkey. Only 774 articles (14.62%) were written as international collaborations. The authors from Turkey were collaborating with the researchers from 66 diffrent countries and USA was leading these countries with 420 publications (%7.93), followed by England (3.3%) and Germany (2.4), respectively. The total number of citations was 53931 for these publications (mean: 10.19±22.51). The most prolific institution is Istanbul University while the most frequently selected journal by Turkish authors is Psychiatry and Clinical Psychopharmacology.
Conclusion: Bibliometric studies are crucial in evaluating domain specific research and in planning for efficient use of limited resources. Psychiatric literature from Turkey greatly increased within the last two decades. However, international collaborations are still limited and most of the publications are in journals published in Turkey.
Keywords: Bibliometric analysis, Turkey, Psychiatric research output
The history of psychiatry is probably as old as that of humanity, although psychiatry as a science is a relatively younger branch of medicine . Mental disorders in ancient times were attributed to supernatural causes and magical rituals were used in healing. Through this time, magicians and religious authorities functioned in treatment [2,3]. Acceptance of psychiatry as a branch of medicine and the onset of contemporary psychiatric practice is a much more recent phenomenon. Actual breakthroughs in psychiatric science had to wait for the emergence of psychopharmacological treatments, construction of a shared language for psychopathology by means of classification systems (e.g. Diagnostic and Statistical Manual of Mental Disorders; DSM, International Classification of Diseases; ICD, Chinese Classification of Mental Disorders, CCMD) as well as innovations in neuroscience and genetics. This period was greatly assisted by increased scholarly output .
Global scientific research output is continuously accelerating. According to a report released in 2015, 2.5 million research articles were published annually . Zhang and colleagues  reported that psychiatric scientific journals published 84760 articles between 2011- 2015, globally. According to the same authors, within the four-year period of evaluation, approximately 17000 articles were published yearly and the research output increased 1.3 times .
Although psychiatric scientific output is increasing, factors such as health systems, scientific programs and financial supports vary between countries leading to varied levels of contribution between countries [6,7]. Zhang and colleagues  reported that the most productive country (among 122) in terms of psychiatric research output in their sample was the USA (32.7 %). United States was followed by the UK (8.6 %), Germany (6.8 %) and Canada (4.9 %). Mean number of citations were ranked as the UK (9.9/ article), the Netherlands (9.8/ article) and the USA (8.8/ article) . Zhang and colleagues  found that 87.7 % of the research output was originated from high-income countries while countries with middle- high (11.1 %) and low- middle (1.0 %) income accounted for much less. Only 0.2 % of the research output was from low income countries. In their list, Turkey was ranked as middle- high income and listed as thirteenth in terms of research output . The dramatic divide in research output across countries according to their income levels was also noted previously by Saxena and colleagues . In a more recent study, Moghadami and colleagues  found that the USA, the UK and Germany were foremost among psychiatric research output listed in SCOPUS database. In that study, the most active institutions were the King’s College in London, the Veterans’ Affairs Medical Center and the Harvard Faculty of Medicine from the USA .
Only one aspect of scientific output may be measured by the number of articles published, however, and scientific efficiency also depends on the quality of articles published. Bibliometric analysis emerged as a novel method to evaluate various aspects of scientific output. This method depends on “bibliometrics” which is defined as application of statistical methods on scientific books, articles and other communication media [9-12]. Bibliometric analysis allows researchers to evaluate scientific output on identified subjects within selected regions, periods and by isolated individuals/ institutions. It also allows evaluations of relationships between those publications and scientific efficiency [11,12]. Bibliometric studies on psychiatric research output as well as on output of allied disciplines from Turkey are relatively limited [13-16]. Therefore, this study aims to evaluate psychiatric research output from Turkey indexed in Web of Science (WoS)and SCI- E index by means of bibliometric methods.
Identification of articles
Using Advanced Search, from the WoS database, articles published in journals classified within the category of Psychiatry were selected (Web of Science Category, WC=Psychiatry). The journals had to be indexed in Science Citation Index- Expanded (SCI-E) database for inclusion. Meeting abstracts, proceedings papers, book chapters, book reprints and early access were excluded as document types. Study period was set as 1980- 2019 and articles from 2020 were also excluded. “Turkey” was selected from the scroll-down menu of Countries/ Regions. At least one of the authors of articles had to be from Turkey for inclusion.
For each publication, all information relevant to the analysis was exported to Microsoft ExcelTM (Microsoft Corp., WA, USA) and a bibliography manager [EndNoteTM Desktop, Clarivate Inc., Philadelphia, PA, USA]. The extracted information included; Author (s), Title, Source, Addresses, Times Cited, and Keywords. VOSviewer software (Version 1.6.15, Centre for Science and Technology Studies, Leiden University, The Netherlands) was used to create a collaboration and word co-occurrence network and to evaluate citation densities . Descriptive analyses were used in summarizing data. Nominal data were summarized as counts and frequencies while quantitative data were summarized as means and standard deviations.
More than five thousand (n= 5293) articles were published in journals in the psychiatry category indexed in SCI-E section of the WoS database between 1980- 2019 in which at least one of the authors were from Turkey. Yearly distribution of articles is illustrated in Figure 1. The majority of the articles were written by a team composed of authors solely from Turkey (n= 4519, 85.4%). Only 774 articles (14.6%) were written as international collaborations. The authors from Turkey were collaborating with the researchers from 66 diffrent countries and USA was leading these countries with 420 publications (%7.93), followed by England (3.3%) and Germany (2.4), respectively. The international collaboration map of the publications is shown in Figure 2.
More than a hundred institutions from Turkey were sources of articles. Ten of the most prolific institutions are listed in Table 1 with institutional collaboration map illustrated in Figure 3. More than half of those institutions were from the largest cities in Turkey (Istanbul, n= 3, Izmir, n= 2, Ankara, n=2) while Elazig, Gaziantep and Manisa were represented by one institution, each. According to VOSviewer analysis, there was a total of 59350 different words in the titles and abstracts of 5293 publications. The distribution map of the 200 most frequently used words in the titles and abstracts is given in Figure 4. The colors used in this figure indicate words within the same topic cluster and distinguishing five colored clusters.
Those articles were published in more than 100 journals. The twenty journals most frequently selected by Turkish authors are listed in Table 2. Psychiatry Clin Psychopharmacol (16.53 %), Anadolu Psikiyatri Derg (16.44 %) and Prog Neuro-Psychopharmacol Biol Psychiatry (3.63 %) were most frequent outlets for Turkish authors. When the fact that Bulletin of Clinical Psychopharmacology changed its name to Psychiatry and Clinical Psychopharmacology in 2016 was considered, that journal emerged as the most frequent outlet for Turkish authors (i.e. n= 875, 16.53 %, Table 2).
More than fifty-thousand citations were made (n= 53931) to the 5293 articles prior to January 2020. Mean number of citations was calculated as 10.19±22.51. More than half of the articles (n= 3779, 71.4%) received at least one citation. Most frequently cited twenty-five articles [18-42] were listed in Table 3, while twenty-five journals most frequently cited were listed in Table 4 and illustrated in Figure 5.
Most commonly cited articles concerned mood disorders (n= 16) and especially depression (n= 10). Oxidative stress and suicidality in depression were evaluated in two studies, each while neurotrophic factors in depression were evaluated in three studies. Other studies concerned oxidative stress in schizophrenia (n=2), neuropsychological features of bipolar disorders (n= 2), magnetic resonance findings in mood disorders (n= 2), treatment of bipolar disorders (n= 2) and alcohol/ substance use disorders (n= 2, Table 3). Most of the frequently cited studies were published in 2005 and 2006 (n= 3, each) and the majority of the frequently cited studies were published from 1997 to 2015 (n=24, 96.0 %).
The most commonly cited journals which published the evaluated articles were Prog Neuropsychopharmacol Biol Psychiatry (9.4 %), Psychiatry Res (5.9 %), Comprehensive Psychiatry (5.5%), J Affect Disord (5.4 %) and Psychiatry Clin Neurosci (4.7 %). Rate of citations to Anadolu Psikiyatri Dergisi- Anatolian Journal of Psychiatry and Klinik Psikofarmakoloji Bülteni- Bulletin of Clinical Psychopharmacology were found to be 3.5 % and 3.0 %; respectively.
Using the VOSviewer software, it was found that more than six thousand key words (n= 6745) were used in the evaluated articles. The most commonly used key words were “depression” (n= 496, 7.4%), “schizophrenia” (n= 470, 7.0%), and “bipolar disorder” (n= 299, 4.4%). Most commonly used keywords according to their clusters is illustrated in Figure 6. Most frequent citations according to authors’ institutions were listed as Istanbul University (n= 7298, 13.5%), Ege University (n= 3729, 6.9%) and Dokuz Eylul University (n= 3681, 6.8%). Top twenty-five author institutions according to number of citations is illustrated in Figure 7.
This study aimed to evaluate psychiatric research output from Turkey indexed in WoS and SCI- E index by means of bibliometric methods. All articles published between 1980- 2019 for which at least one of the authors was from Turkey were eligible for inclusion. As a result, we found that more than five thousand articles were published with a significant increase after 2000 (Figure 1 and Table 3). The majority of articles were written by a team composed solely of Turkish authors and only more than one-tenth were written as international collaborations. Most prolific authors were from Istanbul, Dokuz Eylul and Ege Universities. Most common outlets for publications were Psychiatry Clin Psychopharmacol, Anadolu Psikiyatri Derg and Prog Neuro-Psychopharmacol Biol Psychiatry. More than fifty-thousand citations were made to the articles prior to January 2020. Mean number of citations was calculated as 10.19±22.51. More than half of the articles (71.4%) received at least one citation. Most frequently cited articles addressed mood disorders (especially depression). Most frequently cited articles were published in Prog Neuropsychopharmacol Biol Psychiatry, Psychiatry Res and Comprehensive Psychiatry. Most frequently cited institutions were Istanbul University, Ege University and Dokuz Eylul University.
It is known that science has developed over the course of thousands of years with the contributions of numerous scientists . As a result of scientific and technological innovations, the number of scientific articles published, are increasing daily, especially in the last hundred years. However, psychiatry and allied disciplines display an even greater increase in scientific output [44,10] compared to other disciplines. Larivière and Grant  conducted a bibliometric analysis of 366322 articles from 20 countries published between 1980- 2007 and reported that articles on mental health and disorders increased four-fold within the study period. Evaluations of temporal trends in psychiatric studies from Turkey demonstrated a significant increase in output within the last two decades (Figure 1). Accordingly, we could find 22 articles from Turkey indexed in WoS and SCI-E databases for the year 2000 which increased to 541 for the year 2019 (i.e. an increase of 24.6 times). This elevation may reflect the increased use of web-based services for publication and collaborations among clinicians as well as the introduction of electronic publication services [45,46]. The increase in the number of Turkish higher education institutions within the last two decades as well as the importance of international publications for academic tenure in our country may also have contributed to this finding . Regardless of this increase; Larivière and Grant  reported that psychiatric scientific output of Spain, France, South Korea, Japan and Turkey still lagged behind what is expected of those countries when their total scientific output was evaluated.
Despite the ubiquity of web-based services for collaboration as well as the endorsement of the international collaborations by The Scientific and Technological Research Council of Turkey; the majority of the publications we evaluated included intra-national groups of authors. Along with global research output, international collaborations are also increasing. In study, international collaborations in mental health research was reported to increase to 22.0% for the year 2011 (vs. 3.0% in 1980) . Larivière and Grant reported that Israel, Brazil and Turkey displayed significantly less international collaboration compared to their scientific output and this may reflect the regional dominance of those countries for mental health research . Two studies conducted on scientific output from Turkey reported that although international collaborations were increasing, Turkish authors still chose intra-national colleagues for collaborations over international ones [49,50]. Our results may also support the need for supporting international collaborations of Turkish psychiatrists, child and adolescent psychiatrists and psychologists.
Most prolific as well as the most cited institutions in our study were Istanbul University, Dokuz Eylul University and Ege University. The leading one is located in Istanbul while the remainder are located in Izmir. Both Istanbul and Izmir are located in the western part of Turkey and are major communication, technology and service hubs. This may have increased their scientific output.
The most common journals chosen by Turkish authors for psychiatric research in our study were Psychiatry Clin Psychopharmacol (The journal name Bulletin of Clinical Psychopharmacology changed to Psychiatry and Clinical Psychopharmacology in 2016), Anadolu Psikiyatri Derg and Prog Neuro-Psychopharmacol Biol Psychiatry. The first two journals are located in Turkey which may have affected the authors’ choices. Most frequently cited journals in our study were Prog Neuro-Psychopharmacol Biol Psychiatry (IF= 4.3), J Affect Disord (IF= 4.1) and Psychiatry Res (IF= 2.2) which may expected from their impact factors.
The mean number of citations per article in our study was 10.19±22.51. Igoumenou and colleagues  reported that articles from the USA received the highest number of citations (mean 11.5), followed by the Netherlands (mean 11.4), Canada (mean 9.8) and the UK (mean 9.7). The average number of citations in our study was lower than the USA and the Netherlands while it was higher than Canada and the UK. However, this figure is only correct for the studies we evaluated and Turkish scientific output in mental health as well as total citations received in this domain were repeatedly reported as low in the past [4,8,10]. Besides, the high mean number of citations in our study may be related to the wide time interval. However, Igoumenou et al.  examined only the articles that published between the years 2005-2009. Scientific impact is favorably affected by specialization in a niche topic, structured/ informative abstracts, greater number of references, longer/ detailed reports, inclusion of study design in the title as well as being published as open access [48,51]. Therefore, citations to mental health research from Turkey may be increased by considering those factors as well as increasing international and intra-national collaborations.
Most common keywords for studies evaluated in our research were “depression”, “schizophrenia” and “bipolar disorder”. This may reflect the fact that depression is the commonest psychiatric disorder globally. Global research output on bipolar disorder is rapidly increasing within the last quarter century although literature on this disorder is still patchy compared to that on schizophrenia [52,53]. Research output on schizophrenia is also increasing but its share in total psychiatric output is reducing (from 5.2% to 2.6% within the last 50 years) . Larivière and colleagues  found that research areas varied between countries. According to their results, bipolar and obsessive compulsive disorders were more frequently foci of research from Turkey and that Turkish research output mostly focused on journals covering clinical observations. The last observation may be explained by the greater clinical experience of Turkish clinicians and their lack of access to sophisticated neuroimaging tools .
Our results should be evaluated within their limitations. Firstly, we evaluated studies only from 1980 to 2019 and our results may not be valid for other dates. Secondly, we included studies indexed in WoS and SCI-E databases and not inclusion of other databases may have affected our results. Thirdly, we did not use formal network analysis in evaluating relationships between institutions, journals and keywords . Using formal network analysis methods may have allowed us to determine central and peripheral nodes and strengths of connections as well as separate clusters. Finally, it is known that not all publications in the field of psychiatry are published only in journals scanned in the category of psychiatry. This issue is one of the important limitations of our study.
Bibliometric studies are crucial in evaluating domain specific research and in planning for efficient use of limited resources. This study aimed to evaluate the contribution of Turkish researchers to the psychiatric literature, to determine gaps in research and increase awareness of researchers. Psychiatric literature from Turkey greatly increased within the last two decades. However, international collaborations are still limited and most of the publications were in journals published in Turkey. Citations to studies may also be increased further. Higher education institutions and training hospitals in Turkey may consider interventions to ease both intra-national and international collaborations between researchers focusing on psychiatry. Also, Turkish journals publishing psychiatric research may consider using recent innovations such as social networking etc. to increase global awareness of research from Turkey.
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