title: Frequency doubling perimetry in glaucoma.
abstract: OBJECTIVE
  To evaluate the validity of frequency doubling perimetry (FDP) in the detection of glaucomatous field defects.
  
  
  METHODS
  Group I consisted of 85 eyes of 85 patients with established field defects in automated perimetry, classified by severity of defect. Group II consisted of 48 eyes of 48 control subjects. Both groups underwent Swedish Interactive Testing Algorithm (SITA) standard tests as well as FDP screening strategies (C20-1 and C20-5 and full threshold test). Sensitivity and specificity measures for the FDP tests were calculated using one new and two previously published algorithms.
  
  
  RESULTS
  A described scoring system provided the best sensitivity (85.9%) and specificity (95.1%). For moderate and severe cases, the sensitivity improved to 91%. Quantification of the defect did not improve detection.
  
  
  CONCLUSIONS
  FDP is a valid screening test for glaucoma. The scoring system described by Patel et al. provided the best results.
authors.affiliation: Department of Ophthalmology, Schell Eye Hospital, Vellore, Tamil Nadu, India.
authors.forename: Ravi
authors.initials: R
authors.lastname: Thomas
authors.forename: S
authors.initials: S
authors.lastname: Bhat
authors.forename: J P
authors.initials: JP
authors.lastname: Muliyil
authors.forename: R
authors.initials: R
authors.lastname: Parikh
authors.forename: R
authors.initials: R
authors.lastname: George
mesh_terms: D000328:Adult; D000368:Aged; D002386:Cataract / Q000150:complications; D005260:Female; D005901:Glaucoma / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014786:Vision Disorders / Q000175:diagnosis*; D058609:Visual Field Tests / Q000379:methods*; D014794:Visual Fields