Which Are the Leading Countries in Clinical Medicine Research? A Citation Analysis (1981–1998)
Authors: Giovanni A. Fava, Fedra Ottolini, Nicoletta Sonino
Journal: Psychotherapy and Psychosomatics (2001)

The Institute for Scientific Information (ISI) has developed a database of publication and citation statistics – the National Science Indicators on Diskette (NSIOD) – that reflects scientific research performance of 100 nations during the years 1981–1998. The database includes publications and citations taken from the peer-reviewed journals indexed by ISI. It is designed to analyze the state of research of different countries in different fields. Number of papers published by year, their fate (citations) and the number of citations per paper published (impact) can be analyzed.A citation analysis concerned with the overall field of clinical medicine during 1981–1994 was published in 1996 [1]. It disclosed a clear-cut superiority of the US, UK and Canada. The aim of this paper was to provide an updated (1981–1998) and more detailed survey of the field.The NSIOD database (1981–1998) of the ISI was analyzed. Fifteen fields which were derived from Current Contents/Clinical Medicine were selected for the analysis: general and internal medicine; cardiovascular and respiratory system; gastroenterology; hematology; endocrinology, metabolism and nutrition; rheumatology; environmental and social medicine; clinical immunology and infectious disease; anesthesia and intensive care; surgery; oncology; reproductive medicine; radiology, nuclear medicine and imaging; clinical psychology and psychiatry, and pediatrics. Only 2 fields are reported in detail here. One is general and internal medicine, which includes the papers published in journals such as the Lancet and The New England Journal of Medicine. This is the broadest field. The other is clinical psychology and psychiatry. It includes a selective number of high quality journals with a clinical focus, compared to the general fields of psychology and psychiatry, which have been object of previous publications [2, 3]. It is thus most suited for analyzing the specific contributions of clinical psychology and psychiatry within clinical medicine. For each field the top 20 countries for number of papers in the 18-year period were extracted. Subsequently, their impact (number of citations divided by number of papers) was calculated. Finally, their most recent 5-year impact (1994–1998) was compared with their earliest one (1981–1985).Table 1 provides the data concerning the field of general and internal medicine. The US and the UK, followed by Germany, France and Canada are the top countries for number of papers. However, Swedish papers have the highest impact, and the UK is preceded by the Netherlands and Denmark. Table 2 illustrates the impressive rise of the Netherlands and Scandinavian countries compared to the US and the UK. It is Italy, however, which displays the greatest change in impact. Italy, the Netherlands, Sweden and Belgium have a higher 1994–1998 impact than the US. Figure 1 compares the citation impacts of world regions (US, European Union, Australia and Asia, and Latin America). The American supremacy is not challenged by the European growth.The US and the UK are in the top position both for number of papers and impact in clinical psychology and psychiatry (table 3). Sweden, Ireland and Denmark follow for impact. New Zealand, Germany and Austria have displayed the greatest change in impact (table 4). Figure 2 outlines the citation impacts of the world regions: an impressive growth of Latin America can be observed.These data deserve comment both as to the performance of individual countries and as to problems in assessing research.The main countries included in tables 1, 2, 3, 4 are briefly discussed.United States. The American prominence in medical research appears to be obvious. This is not limited to the fact that the US shows the largest production of papers (around half of the world production) not only in general and internal medicine and clinical psychology and psychiatry, but also in the other 13 fields not reported here. A selection bias of the ISI database may in part be responsible for this prominence. The US has the highest impact in 8 of the 15 fields (cardiovascular and respiratory medicine, gastroenterology, hematology, rheumatology, environmental and social medicine, surgery, radiology, nuclear medicine and imaging, clinical psychology and psychiatry) and ranks at least 3rd in the remaining fields. However, the American superiority is not as strong as it was in the early eighties. There are fields (with pediatrics representing the most striking example), where the growth of American research is inferior to several other countries.United Kingdom. This phenomenon is magnified by British medical research. The UK is 2nd for impact only in clinical psychology and psychiatry, gastroenterology and surgery, whereas the picture was much brighter in the eighties.Canada. The impact of Canadian papers is limited in general and internal medicine and clinical psychology and psychiatry. However, Canada has the highest impact in oncology, reproductive medicine and pediatrics, and is always among the top 10 in the remaining fields. The Canadian impact was also comparatively higher in the eighties.Sweden. It has the highest impact in general and internal medicine and anesthesia and intensive care, and it is always among the top 10 in the remaining fields (3rd in clinical psychology and psychiatry). However, there is a comparative loss of ground in this latter field (table 4), as discussed in detail in previous papers [1, 3].Denmark. It ranks 4th in general and internal medicine (where it shows impressive growth) and 5th in clinical psychology and psychiatry. It is 2nd in endocrinology, metabolism and nutrition and displays the greatest growth in pediatrics.Netherlands. It ranks high in general and internal medicine and in other fields and has the highest impact in clinical immunology and infectious disease.Belgium. It ranks 6th both in general and internal medicine and clinical psychology and psychiatry. However, it shows different progress in the two disciplines (tables 2, 4). It is 3rd in hematology and reproductive medicine.Italy. The case of Italy has been discussed in detail in previous analyses [1, 3]. It shows spectacular growth in general and internal medicine and anesthesia and intensive care and a negative trend in endocrinology, metabolism and nutrition. With France, Germany and Japan it shares the fact of having a large production of papers, which however generate a comparatively low number of citations. This phenomenon has been discussed in detail for psychology and psychiatry [3]and neuroscience [4]. Such a drop, of course, does not take place in every field.France. The impact of French clinical research seems to be very limited. It is among the top 10 countries only in endocrinology, metabolism and nutrition and radiology, nuclear medicine and imaging.Germany. It ranks low as shown in tables 1 and 3, despite a good growth (tables 2, 4). It is among the top 10 only in endocrinology, metabolism and nutrition (10th).Japan. It is among the top 10 only in surgery (10th) and does not even reach the threshold for number of papers in clinical psychology and psychiatry.Switzerland. It is among the top 10 in cardiovascular and respiratory system, gastroenterology and hepatology, endocrinology, metabolism and nutrition (where it ranks first), hematology, rheumatology, clinical immunology and infectious disease, oncology, radiology, nuclear medicine and imaging, and pediatrics.Ireland. It ranks very high and shows much growth in clinical psychology and psychiatry (tables 3, 4); it is among the top 10 in reproductive medicine as well.Australia. It is among the top 10 in general and internal medicine, cardiovascular and respiratory system, gastroenterology and hepatology, endocrinology, metabolism and nutrition, hematology (2nd), rheumatology, environmental and social medicine (2nd), anesthesia and intensive care, surgery, oncology, reproductive medicine, radiology, nuclear medicine and imaging.New Zealand. It displays the highest growth in clinical psychology and psychiatry, and it is 10th in general and internal medicine.Citation analysis, as an indirect measure of the scientific wealth of a nation, has a number of shortcomings. The first concerns the database, that has a clear preference for English language journals. Language discrimination may account for the low citation rates of papers in languages such as German and French, which are included in the database [5]. A second shortcoming involves the fact that comparisons among countries are to some degree confounded, because a large and growing fraction of scientific work involves international collaboration. Finally, analysis of change in impact should be interpreted with caution, since the countries that had the highest impacts in 1981–1985 may display less growth than those which had low impacts during those years. Nonetheless, citation analysis using the ISI database offers a number of helpful indicators for science and policy making [6, 7]. In particular, it may become a helpful tool for unraveling interesting patterns in research which may be correlated with funding priorities. In several European countries, research progress may be hindered by a lack of competing opportunities and control of special interest groups [8], which disregard scientific merit and clinical value. Use of impact factors of journals for evaluating individual research is a misleading tool [9, 10, 11], which lends itself to manipulation. Moreover, citation analysis, in this context, appears to be a fairer and more objective assessment of research than the impact factor as it may be based on several years, which, in many fields, is necessary for disclosing citation patterns of papers which require a certain time before exerting an influence on the scientific literature. The citation analysis of individual countries in clinical medicine has yielded important observations. Substantial differences in performance may reflect a number of phenomena, such as the tradition of fields of excellence, different levels of priorities in investment and efficiency of academic or research institutions. These issues deserve to be discussed and debated at all levels. We welcome comments by our readers.The authors are indebted to Nancy Bayers and David Pendlebury (ISI, Philadelphia) for their help and guidance.