title: The validity of screening for open-angle glaucoma in high-risk populations with single-test screening mode frequency doubling technology perimetry (FDT).
abstract: OBJECTIVE
  To evaluate whether a single frequency doubling perimetry (FDT) test is a valid screening tool to detect open-angle glaucoma (OAG) in high-risk populations.
  
  
  METHODS
  All participants underwent frequency doubling Technology perimetry (FDT C-20-5 algorithm, Carl Zeiss Meditec Inc, Dublin, CA) and complete ophthalmic examination. FDT printouts were classified according to Iwasaki and Patel protocols. Gold-standard was clinical diagnosis of glaucomatous optic nerve damage.
  
  
  METHODS
  Sensitivity, specificity, positive predictive value, negative predictive value, positive, and negative likelihood ratios of a single-test screening FDT.
  
  
  RESULTS
  Data of 445 right eyes and 408 left eyes of participants were analyzed. On the basis of clinical diagnosis, 19 right eyes (4.3%) and 20 left eyes (4.9%) had glaucoma. Depending on the gold standard used, the range of sensitivity was between 40.7% and 78.9%, 66% and 70% for specificity, 7.7% and 25.2% for positive predictive value, 82.3% and 98.6% for negative predictive value, 1.25 and 2.37 for positive likelihood ratio, and 0.32 and 0.87 for negative likelihood ratio. The κ coefficient of agreement between the FDT classifications as described by Iwasaki et al and Patel et al was 0.936 in right eyes and 0.935 in left eyes.
  
  
  CONCLUSIONS
  The sensitivity and specificity of a single reliable screening FDT test were low. Thus, a single screening FDT test in even a high-risk population has poor validity and steps should be taken to better define the target population before testing, and enhance the FDT screening strategy.
authors.affiliation: Department of Ophthalmology, Centre de Recherche de l'Hôpital Maisonneuve-Rosemont, Université de Montréal, Montréal, Quebec, Canada.
authors.forename: Alvine A
authors.initials: AA
authors.lastname: Kamdeu Fansi
authors.forename: Giséle
authors.initials: G
authors.lastname: Li
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Harasymowycz
mesh_terms: D000465:Algorithms; D003430:Cross-Sectional Studies; D005189:False Positive Reactions; D005260:Female; D005902:Glaucoma, Open-Angle / Q000145:classification / Q000175:diagnosis*; D006801:Humans; D007429:Intraocular Pressure; D016013:Likelihood Functions; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014786:Vision Disorders / Q000145:classification / Q000175:diagnosis*; D058609:Visual Field Tests / Q000379:methods*; D014794:Visual Fields