title: Use of a checklist to rule out pregnancy: a systematic review.
abstract: BACKGROUND
  Safe initiation of contraceptive methods requires that pregnancy be excluded. The World Health Organization has developed a list of criteria to assess pregnancy status. This review was conducted to evaluate the evidence regarding these criteria in excluding pregnancy.
  
  
  METHODS
  The PubMed database was searched from database inception through March 2012 for all peer-reviewed articles in any language concerning the performance of a pregnancy checklist compared to urine pregnancy tests. The quality of each study was assessed using the United States Preventive Services Task Force grading system.
  
  
  RESULTS
  Four analyses of data from three studies met inclusion criteria as direct evidence. All were diagnostic accuracy studies of fair quality that evaluated the performance of a pregnancy checklist compared with urine pregnancy test to rule out pregnancy. The performance of the checklist varied, with sensitivity ranging from 55-100% and specificity ranging from 39-89%. The negative predictive value was consistent across studies at 99-100%.
  
  
  CONCLUSIONS
  All four analyses demonstrated high (99-100%) negative predictive value for the pregnancy checklist.
authors.affiliation: Division of Reproductive Health, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA. ntepper@cdc.gov
authors.forename: Naomi K
authors.initials: NK
authors.lastname: Tepper
authors.forename: Polly A
authors.initials: PA
authors.lastname: Marchbanks
authors.forename: Kathryn M
authors.initials: KM
authors.lastname: Curtis
mesh_terms: D057189:Checklist; D003267:Contraception; D005260:Female; D006801:Humans; D011247:Pregnancy; D011258:Pregnancy Tests