title: Assessments of the quality of randomized controlled trials published in International Journal of Urology from 1994 to 2011.
abstract: OBJECTIVE
  Randomized controlled trials are one of the most reliable resources for assessing the effectiveness and safety of medical treatments. Low quality randomized controlled trials carry a large bias that can ultimately impair the reliability of their conclusions. The present study aimed to evaluate the quality of randomized controlled trials published in International Journal of Urology by using multiple quality assessment tools.
  
  
  METHODS
  Randomized controlled trials articles published in International Journal of Urology were found using the PubMed MEDLINE database, and qualitative analysis was carried out with three distinct assessment tools: the Jadad scale, the van Tulder scale and the Cochrane Collaboration Risk of Bias Tool. The quality of randomized controlled trials was analyzed by publication year, type of subjects, intervention, presence of funding and whether an institutional review board reviewed the study.
  
  
  RESULTS
  A total of 68 randomized controlled trial articles were published among a total of 1399 original articles in International Journal of Urology. Among these randomized controlled trials, 10 (2.70%) were from 1994 to 1999, 23 (4.10%) were from 2000 to 2005 and 35 (4.00%) were from 2006 to 2011 (P = 0.494). On the assessment with the Jadad and van Tulder scale, the numbers and percentage of high quality randomized controlled trials increased over time. The studies that had institutional review board reviews, funding resources or that were carried out in multiple institutions had an increased percentage of high quality articles.
  
  
  CONCLUSIONS
  The numbers and percentage of high-quality randomized controlled trials published in International Journal of Urology have increased over time. Furthermore, randomized controlled trials with funding resources, institutional review board reviews or carried out in multiple institutions have been found to be of higher quality compared with others not presenting these features.
authors.affiliation: Department of Urology, Eulji University School of Medicine, Seoul, Korea.
authors.forename: Hee Ju
authors.initials: HJ
authors.lastname: Cho
authors.forename: Jae Hoon
authors.initials: JH
authors.lastname: Chung
authors.forename: Jung Ki
authors.initials: JK
authors.lastname: Jo
authors.forename: Dong Hyuk
authors.initials: DH
authors.lastname: Kang
authors.forename: Jeong Man
authors.initials: JM
authors.lastname: Cho
authors.forename: Tag Keun
authors.initials: TK
authors.lastname: Yoo
authors.forename: Seung Wook
authors.initials: SW
authors.lastname: Lee
mesh_terms: D015706:Bibliometrics; D019317:Evidence-Based Medicine / Q000706:statistics & numerical data*; D006801:Humans; D007564:Japan; D010506:Periodicals as Topic / Q000706:statistics & numerical data*; D011785:Quality Assurance, Health Care; D016032:Randomized Controlled Trials as Topic / Q000592:standards* / Q000706:statistics & numerical data*; D012107:Research Design / Q000592:standards; D012306:Risk; D014572:Urology / Q000706:statistics & numerical data*
keywords: Japan; evidence-based medicine; quality assessment; randomized controlled trial; urology