Comparative study of scientific publications in urology and nephrology journals originating from USA, China and Japan (2001-2010).

Background: In the past decade, scientific research has developed rapidly in China, but the growth seems to vary widely between different disciplines. In this study, we aimed to compare the quantity and quality of publications in urology and nephrology journals from USA, China and Japan.

Methods: Journals listed in the "Urology and Nephrology" category of Science Citation Index Expanded subject categories were included. Scientific papers in these journals written by researchers from USA, Japan and China were retrieved from the "PubMed" and "Web of Knowledge" online databases.

Results: The annual number of total scientific articles increased significantly from 2001 to 2010 in China, and has ranked second in the world since 2006. In the field of urology and nephrology, the annual number increased significantly from 2001 to 2010 in USA and China; but not in Japan. The share of articles increased significantly over time in China, decreased significantly in Japan, and remained unchanged in USA. In 2010, USA contributed 32.17% of the total world output in urology and nephrology field and ranked 1(st); Japan contributed 5.19% and ranked 5(th); China contributed 3.83% and ranked 9(th). Publications from USA had the highest accumulated IFs and the highest total citations of articles (USA>Japan>China, p<0.001). No significant difference was found in average IF among the three countries. USA published the most articles in the top 10 urology and nephrology journals (USA(35165)>Japan(6704)>China(2233), p<0.001). Researchers from USA published more clinical trials and randomized controlled trials than Japan and China (USA>Japan>China, p<0.001).

Conclusion: Although China has undergone significant increase in annual number and percentage of scientific publication in urology and nephrology journals in the past decade, it still lags far behind USA and Japan in the field of urology and nephrology in terms of quantity and quality.