title: Accuracy of cervicovaginal fetal fibronectin test in predicting risk of spontaneous preterm birth: systematic review.
abstract: OBJECTIVE
  To determine the accuracy with which a cervicovaginal fetal fibronectin test predicts spontaneous preterm birth in women with or without symptoms of preterm labour.
  
  
  METHODS
  Systematic quantitative review of studies of test accuracy.
  
  
  METHODS
  Medline, Embase, PASCAL, Biosis, Cochrane Library, Medion, National Research Register, SCISEARCH, conference papers, manual searching of bibliographies of known primary and review articles, and contact with experts and manufacturer.
  
  
  METHODS
  Two reviewers independently selected and extracted data on study characteristics, quality, and accuracy.
  
  
  METHODS
  Accuracy data were used to form 2x2 contingency tables with spontaneous preterm birth before 34 and 37 weeks' gestation and birth within 7-10 days of testing (for symptomatic pregnant women) as reference standards. Data were pooled to produce summary receiver operating characteristic curves and summary likelihood ratios for positive and negative test results.
  
  
  RESULTS
  64 primary articles were identified, consisting of 28 studies in asymptomatic women and 40 in symptomatic women, with a total of 26 876 women. Among asymptomatic women the best summary likelihood ratio for positive results was 4.01 (95% confidence interval 2.93 to 5.49) for predicting birth before 34 weeks' gestation, with corresponding summary likelihood ratio for negative results of 0.78 (0.72 to 0.84). Among symptomatic women the best summary likelihood ratio for positive results was 5.42 (4.36 to 6.74) for predicting birth within 7-10 days of testing, with corresponding ratio for negative results of 0.25 (0.20 to 0.31).
  
  
  CONCLUSIONS
  Cervicovaginal fetal fibronectin test is most accurate in predicting spontaneous preterm birth within 7-10 days of testing among women with symptoms of threatened preterm birth before advanced cervical dilatation.
authors.affiliation: Academic Department of Obstetrics and Gynaecology, Birmingham Women's Hospital, Birmingham B15 2TG. h.honest@bham.ac.uk
authors.forename: Honest
authors.initials: H
authors.lastname: Honest
authors.forename: Lucas M
authors.initials: LM
authors.lastname: Bachmann
authors.forename: Janesh K
authors.initials: JK
authors.lastname: Gupta
authors.forename: Jos
authors.initials: J
authors.lastname: Kleijnen
authors.forename: Khalid S
authors.initials: KS
authors.lastname: Khan
mesh_terms: D015415:Biomarkers / Q000032:analysis; D002584:Cervix Uteri / Q000737:chemistry; D005260:Female; D005353:Fibronectins / Q000032:analysis*; D006801:Humans; D007752:Obstetric Labor, Premature / Q000175:diagnosis*; D011237:Predictive Value of Tests; D011247:Pregnancy; D018566:Pregnancy, High-Risk; D014621:Vagina / Q000737:chemistry
chemical_list: D015415:Biomarkers; D005353:Fibronectins