title: Is there publication bias towards Brazilian articles on cancer?
abstract: OBJECTIVE
  To investigate whether Brazilian articles on cancer are published in journals with an impact factor and/or repercussion (measured by the number of citations) inferior to those that come from foreign organizations.
  
  
  METHODS
  A search was carried out in PubMed for the MeSH term "neoplasm" with the limits clinical trial, affiliation of the Brazilian author(s), and interval from July 1st, 2009 to June 30, 2010. Selected for matching were non-Brazilian related articles published from three months prior to three months after the date of publication of the Brazilian study. The numbers of citations were obtained from two databases, as well as the impact factor for the journals in which the articles were published.
  
  
  RESULTS
  Forty-three national and 876 related international articles were identified. The Brazilian publications had a mean impact factor of 3.000 versus 3.430 of the international ones (p=0.041). There was no statistically significant difference as to the number of citations between the two groups. The affiliation of the first author with a Brazilian or foreign organization did not significantly influence the number of citations or the impact factor.
  
  
  CONCLUSIONS
  Brazilian articles are significantly less accepted in journals with higher impact factors, although it does not compromise its repercussion on the scientific community.
authors.affiliation: Hospital Israelita Albert Einstein, São Paulo, SP, Brasil.
authors.forename: Luiz Victor Maia
authors.initials: LV
authors.lastname: Loureiro
authors.forename: Donato
authors.initials: D
authors.lastname: Callegaro Filho
authors.forename: Altieres de Arruda
authors.initials: Ade A
authors.lastname: Rocha
authors.forename: Bernard Lobato
authors.initials: BL
authors.lastname: Prado
authors.forename: Taciana Sousa
authors.initials: TS
authors.lastname: Mutão
authors.forename: Carlos del Cistia
authors.initials: Cdel C
authors.lastname: Donnarumma
authors.forename: Auro
authors.initials: A
authors.lastname: del Giglio
mesh_terms: D001319:Authorship; D035843:Biomedical Research / Q000706:statistics & numerical data*; D001938:Brazil; D006801:Humans; D055811:Journal Impact Factor; D009369:Neoplasms; D010506:Periodicals as Topic / Q000706:statistics & numerical data*; D017594:Publication Bias / Q000706:statistics & numerical data*; D018709:Statistics, Nonparametric