Altan Onat

Department of Cardiology, Cerrahpaşa Faculty of Medicine, İstanbul University, İstanbul, Turkey


Objective: To identify and disclose publications from Turkey with the greatest “genuine” contributons to medicine in the past 50 years.

Material and Methods: Based on the data of Web of Science, publications originating from Turkey's institutions that were received by May, 2013, ≥72 citations were identified, after excluding papers having more than a minor share by international authors.

Results: Primary authors numbering 223 generated 271 medical papers, each receiving ≥72 (95% CI 72; 263) citations. The articles cited herein were of a level of top global 8-10% papers. Half of the articles were published in 1997-2004. Compared with about 25-28 papers annually 10 years previously, it is estimated that currently only 20 papers are generated in Turkey annually, representing a global share of only 1.5 per thousand. The rate of rise registered in the period 1995-2004 may be anticipated to attenuate. Internal medicine, led by rheumatology, cardiology and hematology, and neurosciences were represented at 1.8-fold odds higher than the overall average. Led by Behçet's disease, health issues encountered more widely than in other populations, formed frequent topics of contribution. Led by the Medical Faculties of Istanbul, Hacettepe, Ankara Universities and the Military Medical Academy, only 33 medical faculties and 14 public and private hospitals constituted sources.

Conclusion: Since the elicited results are unsatisfactory, compared with Turkey's potential, much more concerted efforts should be directed to rebuild a milieu favorable to promote research likely to contribute to medicine.

Keywords: Contribution to medicine, history of medicine, medical research in Turkey


Health, the most vital aspect of life, represents the basis for development and welfare. Progress in medicine is indispensible for both protecting health and treating its impairment. Hence, it is highly desirable for communities to track the contributions to medicine closely. Among various indicators of scientific contributions, the total number of publications, number of papers in periodicals of exceptionally high impact, or the total number of citations to an article have been used. In view of high heterogeneity in both the quality of a given scientific paper, and the factors associated with the overall number of citations received, it is generally held that highly-cited papers, such as the top 1% of all articles in a field receiving the highest cites, better reflect the contribution[1]. Indeed, a criterion of 10% of papers with highest citations have been utilized in the Leiden Ranking of world universities[2]. The real contribution of the individual author or institution is diluted among the growing proportion of publications with international collaboration, such as clinical trials, meta-analyses, guidelines or scientific statements that receive high numbers of citations, and necessitates the consideration of a second aspect for this task. The “genuine” contribution of the native researcher in such papers may be near-negligible.

These considerations suggest that a method previously proposed by this author, namely, the generation of research attaining citations above a relatively high threshold in institutions of a native country may be most appropriate to evaluate, especially for countries not in a leading position in science[3,4]. The present paper aims to investigate the contribution to medicine of research generated in Turkey by its scientists in the past half-century, utilizing a method of highly-cited articles that correspond to about 7-10% of global papers in their fields. The magnitude, period and rate of change over time, distribution across medical institutions and fields, the individual publication references and scientists are herein evaluated.

Material and Methods

Citation data were derived from Thomson Reuters Web of Science, using “Turkey” as the address. Publications in science and technology in the past half-century were listed by the number of attained citations. Over 2100 items, found to have been cited 72 or more times, have been screened for the field of medicine. The criterion was further to be met of having more than a minor international share, which was specifically indicated by having all of the first three authors of the paper work in a Turkish university or hospital.

In co-authored papers with multiple institutions, the first author and his/her institution were credited and listed. With the purpose of precluding omission of some researchers in the address “Turkey”, some scientists known to me from previous work were individually searched[4]. For those authors who produced highly-cited papers in two different institutions, citations received were assigned to the two institutions.

Reported data of Web of Science in the current study pertain to those available in early May, 2013. It is known that these Web of Science data exclude intrinsically eligible citations to references incorrectly or inadequately provided and to periodicals not covered by the Web of Science. These excluded citations may be estimated to form a share of 5% to 10% of the Web of Science citations.


A total of 271 medical papers were identified generated in Turkey's institutions that received 72 or more cited. The total number of citations received by these papers was 29,212. Publication year of the papers ranged from 1971 to 2009, had a median of May, 2001 (interquartile range August, 1997 and Sptember, 2004). This indicated an exposure period of a median of 12 (IQR 7½ to 15) years. Source information to these articles are presented in Table 1.

Distribution by fields in medicine
Table 2 lists publications and citations categorized to the medical fields. The share of citations was 43% for internal medicine, 18% for neurosciences; these represented above-average performance when compared with the global mean share. Instead of an expected share of 21% and 36% for surgery and basic sciences, respectively, these major fields attained a performance slightly below average, attaining shares of 16% and 21%, respectively. With a production of 8 papers alone, pediatrics displayed a performance clearly below-average.

Among internal medical sciences, rheumatology with 25 papers, cardiology and hematology each with 14, endocrine and metabolism with 10 papers were placed in the lead . Neurology (25) and psychiatry (21 articles) also exhibited successful performance. Biochemistry led with 22 papers in basic sciences.

Journals of preference
Though evaluated papers were published in approximately 160 different journals, a dozen journals were the ones to attract most of these highly-cited papers. Clin Biochem with 7, Ann Rheum Dis with 6, Clin Chim Acta, Fertil Steril, Hum Reproduct, J Clin Endocrinol Metab, J Rheumatol, J Urol, Stroke, Thorax each with 5, and Arthritis Rheum and Rheumatol Int each with 4 papers, ranked foremost. Noteworthy is that the great majority of the stated journals belong to periodicals with intermediate (2 ila 7) rather than high impact factors.

Sources confined to 48 institutions
Only 33 medical faculties, Gülhane Military Academy (GATA) and 14 public and private hospitals generated the herein studied papers (Table 3). The majority of citations were received by the Medical Faculties of the Universities of Hacettepe, Istanbul (Cerrahpaşa and İstanbul faculties), Ankara and GATA. These were followed by the Aegean, Harran, Erciyes, Dokuz Eylül, Akdeniz and Inönü University medical faculties, each with 7-13 publications. Researchers working in hospitals outside the medical faculties shared 5.7% of total citations.


The current study incorporates 2½ to 3-fold the number of papers and citations than a previous report of mine[3], due both to including two more recent years and selecting a lower threshold by 10 citations. Hence, the significance of the analyses is higher, and it is also more updated. A total of 271 papers originating from Turkey and half of them published in the period 1997 to 2004, has each succeeded in receiving 72 to 348 cites. Since, in the stated period, worldwide published annual medical papers of an equivalent level can be estimated to range around 15-18,000, the generation in Turkey of 25-28 articles each year (Figure 1) corresponds to a global share of 1.5 per thousand. Such a performance cannot be considered satisfactory, given Turkey's potential.

The majority of best research originates from established faculties
Nine out of 10 highly-cited medical publications derived from only 19 medical faculties, GATA and a hospital affiliated with the Health Ministry, indicating that the distribution of fundamental research is highly concentrated in Turkey. As anticipated, the medical faculties of established universities were leading this list. Beyond them, GATA, Harran, İnönü, Kocaeli, Süleyman Demirel, Mersin, Gaziantep, Trakya Universities. Medical Faculties were notable for contributions and surpassed certain more ancient faculties. Nonetheless, it should be questioned why criteria stipulated in this study were not met by a faculty founded in the past 20 years.

Topics and areas suited to have attained success
Obviously, topics of the research papers were highly diverse. Interested readers may be inspired by the information contained in Table 1. Highly-cited papers tend to be concentrated in certain areas led by Behçet's disease (with 36 papers), a finding not surprising but deserving appreciation. Topics related to oxidation and antioxidants followed with 20 papers. Hydatid cysts, depression, familial Mediterranean fever, chronic benzene toxicity, polycystic ovary syndrome and schizophrenia constituted areas with 5 to 10 contributing papers each.

With the purpose of attaining a high number of citations, it should be underlined here that, apart from the impact factor of the journal, the incremental value added by the investigation published is of great relevance. Indeed, numerous papers published in upper-mid category of journals have succeeded in being highly-cited, specifically twice as much as the impact factor of the related journals.

Leading individual scientists
Table 4 lists 28 primary authors who, with a total of 76 papers, have generated more than one highly-cited paper. Two of these scientists are deceased, namely, hematologists Muzaffer Aksoy with 8 and the neuropsychiatrist S. Akpınar with 2 papers. Biochemists Özcan Erel and İlker Durak, cardiologist Altan Onat, rheumatologist Hasan Yazıcı and Vedat Hamuryudan and Sabahattin Yurdakul from his group; rheumatologist Ahmet Gül, neurologists Murat Emre and Piraye Serdaroğlu, as well as the infection specialist Ömer Ergönül have each collected over 300 high-citations with their publications. Furthermore, oncologists Yener Koç and M. Altınbaş, neurologist Gülşen Akman- Demir, cardiologist Adnan Abacı, pneumologist A. C. Öğüş, psychiatrist M. Bilici and rheumatologist Emire Kural-Seyahi have attained over 200 cites each by a single publication.

Extrapolating data provided by the Scientific Paper Indicators ULAKBİM[5], it may be estimated that, in the course of 30 years following 1981, approximately 80,000 publications were produced in medicine in Turkey that received roughly 300,000 cites. Highly-cited papers referred to in this study, whilst representing 1 of every 300 overall papers generated, received onetenth of overall citations in medicine.

Are we experiencing stagnation recently?
It may be predicted that no more than an annual average of 20 articles will be produced after 2004, although a yearly mean of 25-28 articles made this cut in the period 1998-2004. I base this estimate on data of the SCI indicating that, of all the cites to be received by a paper, one-quarter will be received in the 3 years following publication and half of them in the first 6-7 years. This implies that stagnation or even a decline may be observed with respect to generating research contributing to medicine; overlooking this development may have serious consequences.

Considering that the majority of the numerous recentlyfounded medical faculties are not at a level to produce papers contributing to medicine, it is mandatory that new regulations and incentives should be made in the education and science policy nationwide. Currently, the great majority of Turkey's international publications appear in journals with a low impact factor[6]. While eliminating the current tedious formalities associated with funding research, elaborate administrative incentives need to be created, both materially and in spirit, to promote in-depth research having the potential of contributing to medicine.


In summary, only 271 publications have been generated in Turkey in the past half-century that had the potential to contribute to medicine. The annual production capacity of 25-30 papers appears to have declined to 20 papers in recent years. This is a considerably lower-than- satisfactory performance for Turkish medical faculties which incorporate nearly 40,000 academic personnel and a teaching staff of around 16,000. The opinion should be expressed, in conclusion, that an environment needs to be urgently constructed by authorities that focuses on promoting research of a level contributing to medicine.

Conflict of Interest
No conflict of interest was declared by the author.

Peer-review: Externally peer-reviewed.

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