title: Findings from the National Birth Defects Prevention Study: Interpretation and translation for the clinician.
abstract: BACKGROUND
  The National Birth Defects Prevention Study (NBDPS) is a large U.S. multi-site case-control study first established in 1996 to identify potentially preventable environmental causes and genetic risk factors for more than 30 selected categories of major birth defects.
  
  
  METHODS
  Numerous reports with both positive and negative findings have been produced by the NBDPS, and many have influenced clinical practice. Many NBDPS reports have included novel findings, and in some cases these findings could only be considered hypothesis-generating. Other reports have met criteria for causality such as replication of findings in other studies, biological plausibility, and coherence.
  
  
  RESULTS
  However, translation of even strongly supported associations, in some cases, has required clinicians to learn to communicate information to patients about small and uncertain absolute risks in the context of the potential effects of under- or poorly treated maternal conditions.
  
  
  CONCLUSIONS
  The NBDPS has continued to play an important role as a rich U.S. data source that can advance the understanding of maternal conditions and their treatments in relation to birth defects.
authors.affiliation: Department of Medical Genetics, University of British Columbia, Vancouver BC, Canada.
authors.forename: Sura
authors.initials: S
authors.lastname: Alwan
authors.affiliation: Department of Pediatrics, University of California, San Diego, La Jolla, California.|Department of Family Medicine and Public Health, University of California, San Diego, La Jolla, California.
authors.forename: Christina D
authors.initials: CD
authors.lastname: Chambers
mesh_terms: D016022:Case-Control Studies; D000013:Congenital Abnormalities / Q000209:etiology* / Q000517:prevention & control*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D018811:Maternal Exposure / Q000009:adverse effects*; D010819:Physician's Role; D011159:Population Surveillance; D017410:Practice Guidelines as Topic; D012307:Risk Factors
keywords: birth defects; case-control study; communication of risk; pregnancy and lactation labeling rule