title: [Quality of clinical studies published in the RBGO over one decade (1999-2009): methodological and ethical aspects and statistical procedures].
abstract: OBJECTIVE
  To evaluate the methodological and statistical design evolution of the publications in the Brazilian Journal of Gynecology and Obstetrics (RBGO) from resolution 196/96.
  
  
  METHODS
  A review of 133 articles published in 1999 (65) and 2009 (68) was performed by two independent reviewers with training in clinical epidemiology and methodology of scientific research. We included all original clinical articles, case and series reports and excluded editorials, letters to the editor, systematic reviews, experimental studies, opinion articles, besides abstracts of theses and dissertations. Characteristics related to the methodological quality of the studies were analyzed in each article using a checklist that evaluated two criteria: methodological aspects and statistical procedures. We used descriptive statistics and the χ2 test for comparison of the two years.
  
  
  RESULTS
  There was a difference between 1999 and 2009 regarding the study and statistical design, with more accuracy in the procedures and the use of more robust tests between 1999 and 2009.
  
  
  CONCLUSIONS
  In RBGO, we observed an evolution in the methods of published articles and a more in-depth use of the statistical analyses, with more sophisticated tests such as regression and multilevel analyses, which are essential techniques for the knowledge and planning of health interventions, leading to fewer interpretation errors.
authors.forename: Joceline Cássia Ferezini
authors.initials: JC
authors.lastname: de Sá
authors.forename: Gabriela
authors.initials: G
authors.lastname: Marini
authors.forename: Rafael Bottaro
authors.initials: RB
authors.lastname: Gelaleti
authors.forename: João Batista
authors.initials: JB
authors.lastname: da Silva
authors.forename: George Gantas
authors.initials: GG
authors.lastname: de Azevedo
authors.forename: Marilza Vieira Cunha
authors.initials: MV
authors.lastname: Rudge
mesh_terms: D035843:Biomedical Research; D001938:Brazil; D006176:Gynecology; D010506:Periodicals as Topic; D011643:Publishing / Q000941:ethics* / Q000592:standards / Q000706:statistics & numerical data*; D013997:Time Factors