title: National laboratory reports of Chlamydia trachomatis seriously underestimate the frequency of genital chlamydial infections among women in Switzerland.
abstract: BACKGROUND
  Public health authorities want to evaluate their sexually transmitted disease (STD) surveillance systems to promote the most effective use of health resources.
  
  
  OBJECTIVE
  The goal of this study was to estimate the sensitivity of national laboratory reports of in Switzerland (the proportion of cases detected by national laboratory reports).
  
  
  METHODS
  A cross sectional prevalence study was conducted by the Swiss Sentinel Surveillance Network of Gynecologists in 1998. Two groups of women aged less than 35 years were included in the study: those having a first consultation for pregnancy and those having a routine check-up.
  
  
  RESULTS
  A total of 1589 women were tested for. The prevalence among pregnant women (n = 817) was 1.3%, and that among sexually active women (n = 772) was 2.8%. Using the prevalences observed among check-up women, we estimate that there were at least 24,400 infections in Switzerland among women aged 20 to 34 years in 1998 (95% CI: 14,300-34,300). The number of laboratory reports of in this age group was 1,150 in 1998.
  
  
  CONCLUSIONS
  Our study suggests that the sensitivity of national laboratory reports of in 1998 was less than 5% for women aged 20 to 34 years.
authors.affiliation: Swiss Federal Office of Public Health, Bern, Switzerland.
authors.forename: W John
authors.initials: WJ
authors.lastname: Paget
authors.forename: Reinhard
authors.initials: R
authors.lastname: Zbinden
authors.forename: Eva
authors.initials: E
authors.lastname: Ritzler
authors.forename: Marcel
authors.initials: M
authors.lastname: Zwahlen
authors.forename: Christian
authors.initials: C
authors.lastname: Lengeler
authors.forename: Dieter
authors.initials: D
authors.lastname: Stürchler
authors.forename: Hans C
authors.initials: HC
authors.lastname: Matter
mesh_terms: D000328:Adult; D000847:Annual Reports as Topic; D002690:Chlamydia Infections / Q000453:epidemiology*; D002692:Chlamydia trachomatis / Q000302:isolation & purification; D003430:Cross-Sectional Studies; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007753:Laboratories / Q000706:statistics & numerical data*; D011159:Population Surveillance; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000453:epidemiology; D015995:Prevalence; D012680:Sensitivity and Specificity; D013557:Switzerland / Q000453:epidemiology