title: Hematology research output from Chinese authors and other countries: a 10-year survey of the literature.
abstract: BACKGROUND
  Hematologic disease affects people of all ages worldwide. In the past decade, researchers have made great progress in the field of hematology. In the present study we compared the hematology research output from China and other countries (USA, Germany, UK, Japan and South Korea) over the past 10 years and 5 years.
  
  
  METHODS
  The related articles were extracted based on the PubMed database. We recorded the number of publications, clinical trials, randomized controlled trials, meta-analyses, case reports, reviews, citations, impact factors, articles in the top 10 journals and most published journals to assess the quantity and quality of research output in each region.
  
  
  RESULTS
  A total of 120,641 hematology-related articles were published from 2004 to 2013. The USA accounted for 27.13% (32,732/120,641) of the publications, followed by Germany (7,479/120,641; 6.20%), Japan (6,347/120,641; 5.26%), the UK (5,453/120,641; 4.52%), China (2,924/120,641; 2.42%) and South Korea (1,413/120,641; 1.17%). The ranking for cumulative impact factors was as follows: USA; Germany; UK; Japan; China and South Korea. The median impact factors in the UK, USA, and Germany were higher than Japan, South Korea, and China. Interestingly, the median impact factors in the three Asia countries were similar both in 2004-2013 and 2009-2013. The UK had the highest percentage of publications in the top 25% of journals, while China lagged behind and ranked last. When comparing the number of articles in the top 10 journals, the results were similar to the IF findings. Germany had the highest number of average citations, while China had the lowest number of average citation. The status of hematology research output from the 6 countries in 2009-2013 had little difference from 2004-2013.
  
  
  CONCLUSIONS
  Thus, the USA has had a dominant role in hematologic research in the past 10 years. Overall, the quality of publications in European countries was better than Asia countries. Although China has made considerable progress in hematology research, the quality of research needs improvement.
authors: Department of Laboratory Diagnosis, Changhai hospital, Second Military Medical University, Shanghai, 200433, China. 448342971@qq.com.
authors: Lei
authors: L
authors: Zhang
authors: Department of Transfusion Medicine, Changhai hospital, Second Military Medical University, Shanghai, 200433, China. yexin0223@hotmial.com.
authors: Xin
authors: X
authors: Ye
authors: Department of Laboratory Diagnosis, Changhai hospital, Second Military Medical University, Shanghai, 200433, China. 1364468333@qq.com.
authors: Yi
authors: Y
authors: Sun
authors: Department of Laboratory Diagnosis, Changhai hospital, Second Military Medical University, Shanghai, 200433, China. amdeng70@163.com.
authors: An-mei
authors: AM
authors: Deng
authors: Department of Transfusion Medicine, Changhai hospital, Second Military Medical University, Shanghai, 200433, China. qianbh1963@163.com.
authors: Bao-hua
authors: BH
authors: Qian
mesh_terms: D035843:Biomedical Research / Q000706:statistics & numerical data / Q000639:trends*; D002681:China; D005858:Germany; D006405:Hematology / Q000706:statistics & numerical data / Q000639:trends*; D006801:Humans; D007564:Japan; D055811:Journal Impact Factor; D056910:Republic of Korea; D011795:Surveys and Questionnaires; D006113:United Kingdom; D014481:United States
references: Science. 2008 Oct 10;322(5899):191
references: 18845732
references: Science. 2008 Dec 5;322(5907):1463
references: 19056954
references: Lancet. 2013 Jun 8;381(9882):1984
references: 23746898
references: Lancet. 2013 Jun 8;381(9882):1987-2015
references: 23746901
references: JAMA. 2014 Sep 10;312(10):999-1000
references: 25203078
references: Lancet. 2014 Sep 13;384(9947):956
references: 25220974