title: Japan's contribution to clinical pediatrics research in the last decade.
abstract: OBJECTIVE
  To determine Japan's contribution to research in clinical pediatrics over the last decade.
  
  
  METHODS
  Articles published in highly reputable pediatrics journals from 1991-2000 were accessed through the MEDLINE database. The number of articles which had an affiliation with a Japanese institution were counted for each of the journals and also summed in total. Proportions of randomized controlled trials (RCTs) and case-control/cohort studies among the articles from Japan were also generated and compared with the average for the entirety. In addition, shares of the top-ranking countries were presented along with their trend over time.
  
  
  RESULTS
  In total, 20 189 articles were published in the selected seven pediatric journals from 1991-2000. Japan contributed 3.0% of these articles and this contribution was ranked 7th in the world. A negative trend was noticed in Japan's contribution over time but it was not statistically significant (z = -0.40, P = 0.16). RCTs accounted for 7.3% of the total articles, but only 0.34% of those from Japan.
  
  
  CONCLUSIONS
  Japan's share of articles in pediatrics research was smaller than that in basic science and some of the other clinical fields. The number of articles from Japan providing a high level of evidence was meager in this field.
authors.affiliation: Department of General Medicine and Clinical Epidemiology, Kyoto University Graduate School of Medicine, Kyoto, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Okamoto
authors.forename: Mahbubur
authors.initials: M
authors.lastname: Rahman
authors.forename: Tsuguya
authors.initials: T
authors.lastname: Fukui
mesh_terms: D015706:Bibliometrics; D002648:Child; D006801:Humans; D007564:Japan; D016239:MEDLINE; D010372:Pediatrics; D012106:Research / Q000706:statistics & numerical data*; D018709:Statistics, Nonparametric