INT J TUBERC LUNG DIS 19(6):717–722 Q 2015 The Union http://dx.doi.org/10.5588/ijtld.14.0925 The 100 top-cited tuberculosis research studies L.-M. Chen,*† Y.-Q. Liu,* J.-N. Shen,* Y.-L. Peng,* T.-Y. Xiong,* X. Tong,‡ L. Du,*§¶ Y.-G. Zhang*§¶ *West China Hospital, West China Medical School, Sichuan University, Chengdu, †Department of Anaesthesiology, West China Hospital of Sichuan University, Chengdu, ‡Department of Respiratory Medicine, West China Hospital of Sichuan University, Chengdu, §The Periodical Press of West China Hospital, Sichuan University, Chengdu, ¶The Chinese Cochrane Centre, West China Hospital, Sichuan University, Chengdu, China SUMMARY The examination of top-cited studies is a useful method ing author. The United States contributed the largest for identify and monitoring outstanding scientific number of studies, followed by the United Kingdom and research. The objective of this study was to identify France. The institutions with the largest number of and analyse the characteristics of the top 100 cited articles were the Institut National de la Santeetdela´ research studies on tuberculosis (TB) based on the Web Recherche Medicale´ in France and the University of of Knowledge. Overall, the top 100 cited studies were California in the United States. The studies appeared in cited between 366 and 4443 times, and were published 35 journals, with 11 published in Science, followed by between 1995 and 2010, with the largest number of PNAS and NEJM. The majority of TB articles have been publications in 2003 and in 1995. Four studies were published in those medical journals with the highest attributed to a single author and 10 to two authors; the impact factors, and are from the most industrialised number of authors exceeded six in 50 studies. Nine countries. authors had more than one study as the first author and KEY WORDS: tuberculosis; citation; top-cited studies 18 authors had more than one study as the correspond- THE MOST WIDELY USED METHOD for evalu- issues in TB.16–20 To our knowledge, no citation ating the academic importance of a study in a analysis has been published in the field of TB. specific area of knowledge is determining how many The objective of the present study was to use the times the study has been cited by other researchers.1 bibliometric resources of the Web of Science to identify It is well known that the number of citations for a the 100 most cited studies published on TB and to study might express the potential of the study for analyse their principal characteristics.21 This is, to our clinical practice, discussion, controversy or further knowledge, the first bibliometric analysis of TB studies. research.2 Citations analysis has become a useful method for assessing the quality, trend and future of METHODS some research fields.1,3,4 Although citations analyses Two independent reviewers (LMC and TYX) from the Science Citation Index ExpandedTM of the searched TB studies using the cited reference search Web of ScienceTM (Thomson Reuters, Philadelphia, tool of the Web of Knowledge in the Web of Science’s PA, USA) in recent years have enabled researchers to core collection. A topic search with the terms ‘tuber- assess the importance of research in areas such as culo*’ or ‘tuberculosis’ or ‘TB’ was conducted, and obstetrics and gynaecology, emergency medicine, search results sorted by number of citations. The 2,5–7 urology and orthopedics, many new studies, following inclusion criteria were used: 1) studies that such as research on tuberculosis (TB) studies, remain reported mainly on TB disease or on Mycobacterium to be conducted. tuberculosis; and 2) studies that were articles, TB is one of the most common causes of death due reviews, editorials or research letters. The exclusion to an infectious disease,8–12 and is an important criteria were as follows: 1) studies that mentioned the subject of medical research.13–15 Studies related to word ‘tuberculosis’ but did not deal with TB; and 2) pathology, physiopathology, diagnosis, manifesta- abstracts, corrigenda/errata, correspondence. Any tions, treatment, prognosis, prevention, epidemiology disagreements were resolved by discussion or decided and patient education are the most widely studied by the third author (YQL). Correspondence to: Liang Du or Yong Gang Zhang, The Periodical Press of West China Hospital, Sichuan University, Chengdu 610041, China. Tel/Fax: (þ86) 28 8542 2052. e-mail: [email protected]; [email protected]. Article submitted 6 December 2014. Final version accepted 21 January 2015. 718 The International Journal of Tuberculosis and Lung Disease Table 1 Authors with more than one study as first or infection or TB disease. The third most cited study corresponding authors included in the 100 top-cited studies was a report published in JAMA in 1999 by Dye et al. Studies on the global burden of TB.24 Author Name n Corresponding author Behr, M A 2 Author distribution Casanova, J L 2 Four articles were attributed to a single author and 10 Cooper, A M 2 Dye, C 3 to two authors; the number of authors exceeded six in Flynn, J L 3 50 studies. Authors with more than one study as the Franzblau, S G 2 first author or corresponding author have been listed Friden, T R 2 Hill, A V S 2 in Table 1. Nine authors had more than one study as Modlin, R L 4 the first author, and 18 had more than one study as Musser, J M 2 the corresponding author. The author with the largest Nathan, C F 2 Pai, M 2 number of studies as corresponding author was Rubin, E J 2 Modlin (n ¼ 4). Russell, D G 2 Stover, C K 2 Supply, P 2 Country distribution van Embden, J D 2 The country of the corresponding author was used to Wayne, L G 2 First author Behr, M A 2 analyse country contributions on TB (Table 2). Dye, C 2 Briefly, the top 100 cited studies were from 13 Flynn, J L 2 countries (Argentina, Belgium, Canada, Denmark, Friden, T R 2 Pai, M 2 the United Kingdom, France, Germany, Japan, the Sassetti, C M 2 Netherlands, South Africa, Spain, Switzerland and Stenger, S 2 the United States) and one international organization Supply, P 2 Wayne, L G 2 (World Health Organization [WHO]). The country with the most top cited studies was the United States, with 58 studies, followed by the United Kingdom We identified the 100 top cited studies by number of with 11 and France with 6. The country with the most citations on 10 January 2015. The following informa- citations was the United States, with 33 673 citations, tion was extracted for each study: number of citations, followed by the United Kingdom, with 9498 cita- first author, corresponding author, number of authors, tions. The countries with most citations on average publication name, year, country of origin and number were the United Kingdom, with 864, followed by of pages. Country of origin was determined on the Argentina, with 828. basis of the country of the first author. Institutional distribution To analyse contributions from institutions, those with RESULTS at least two studies based on the first address of the Main characteristics of the included studies corresponding author were examined (Table 3). The Appendix Table* shows the characteristics of the Eighteen institutions with more than two studies top 100 cited studies in TB research in descending were included. The institutions with the largest order. The number of citations varied between 366 number of articles were the Institut National de la and 4443, with a total of 62 801. All of the first 11 Sante´ et de la Recherche Medicale´ (INSERM) (n ¼ 6) studies exceeded 1000 citations each, and the first 46 in Paris, France, and the University of California (n ¼ had more than 500 citations each. It is possible to 6) in the United States, followed by the University of comment only on three of the most relevant articles Oxford, Oxford, UK (n ¼ 5), the WHO, Geneva, here. The most cited study (4443 citations) was a Switzerland (n ¼ 5), and Cornell University, Ithaca, research study about the complete genome sequence NY, USA (n ¼ 5). of M. tuberculosis, published in 1998 by Cole et al. in Distribution by year of publication Nature.22 The second study (1881 citations), on TB associated with infliximab, was published in 2001 by The distribution by year of publication of the top 100 Keane et al in NEJM.23 The study reported that as cited studies is shown in Table 4. The top-cited studies active TB could develop soon after the initiation of were published between 1995 and 2010. The years treatment with infliximab, physicians could use the with the most studies were 2003 and 1995, with 11 drug to screen patients for latent tuberculous studies each, followed by 1998 and 2001, with 10 each. The year with the most citations was 1998, with * The Appendix is available in the online version of this article, 9007 citations, followed by 2003, with 6858. The at http://www.ingentaconnect.com/content/iuatld/ijtld/2015/ year with the most citations on average was 1998, 00000019/00000006/art00020 with 901, followed by 2007, with 742. Top-cited TB researches 719 Table 2 Country of origin of the 100 top-cited studies; based on country of first author Studies in each ranking, Total Average n Studies citations citations/article Country n N n 1~10 11~20 21~30 31~40 41~50 51~60 61~70 71~80 81~90 91~100 Argentina 1 828 828 1 Belgium 1 674 674 1 Canada 5 2 842 568 1 1 1 1 1 Denmark 2 800 400 1 1 France 7 3 370 481 1 1 1 2 2 Germany 1 421 421 1 Japan 1 395 395 1 Netherlands 4 2 916 729 1 1 1 1 South Africa 1 372 372 1 Spain 1 490 490 1 Switzerland 2 1 377 689 1 1 United Kingdom 11 9 498 864 1 2 1 1 1 2 1 2 United States 58 33 673 581 5 5 7 6 6 6 7 5 7 4 WHO 5 5 145 1 029 3 1 1 WHO ¼ World Health Organization.