title: American College of Obstetricians and Gynecologists practice bulletins: an overview.
abstract: OBJECTIVE
  The purpose of this study was to review the American College of Obstetricians and Gynecologists practices bulletins to quantify the type of recommendations and references and determining whether there are any differences between obstetric and gynecologic bulletins.
  
  
  METHODS
  All practice bulletins published from June 1998 to December 2004 were reviewed. Odds ratios and 95% confidence intervals were calculated.
  
  
  RESULTS
  The 55 practice bulletins contained 438 recommendations of which 29% are level A, 33% level B, and 38% level C. The 55 bulletins cite 3953 references of which 17% are level I, 46% level II, 34% level III, and 3% others. Level A recommendations were significantly more likely among the 23 gynecologic than 32 obstetric bulletins (37% versus 23%, odds ratios 1.95, 95% confidence intervals 1.28, 2.96). The study types referenced in obstetric and gynecologic bulletins were similar (P > .05 for comparison of levels I, II, and III and meta-analysis references).
  
  
  CONCLUSIONS
  Only 29% of the American College of Obstetricians and Gynecologists recommendations are level A, based on good and consistent scientific evidence.
authors.affiliation: Division of Maternal-Fetal Medicines, Aurora Health Care, West Allis, WI, USA.
authors.forename: Suneet P
authors.initials: SP
authors.lastname: Chauhan
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Berghella
authors.forename: Maureen
authors.initials: M
authors.lastname: Sanderson
authors.forename: Everett F
authors.initials: EF
authors.lastname: Magann
authors.forename: John C
authors.initials: JC
authors.lastname: Morrison
mesh_terms: D019317:Evidence-Based Medicine; D006176:Gynecology; D006801:Humans; D009774:Obstetrics; D017410:Practice Guidelines as Topic / Q000592:standards*; D012955:Societies, Medical; D014481:United States