title: A new color vision test to differentiate congenital and acquired color vision defects.
abstract: OBJECTIVE
  To investigate the efficacy of a novel computer-controlled color test for the differentiation of congenital and acquired color vision deficiency.
  
  
  METHODS
  Observational cross-sectional study.
  
  
  METHODS
  Thirty-one patients with congenital color vision deficiency and 134 patients with acquired color vision deficiency with a Snellen visual acuity better than 20/30 underwent an ophthalmologic examination including the Ishihara color test, Hardy-Rand-Rittler test, Nagel anomaloscopy, and the Seohan computerized hue test between June, 2003, and January, 2004.
  
  
  METHODS
  To investigate the type of color vision defect, a graph of the Seohan computerized hue test was divided into 4 quadrants and error scores in each quadrant were summated. The ratio between the sums of error scores of quadrants I and III (Q1+Q3) and those of quadrants II and IV (Q2+Q4) was calculated.
  
  
  METHODS
  Error scores and ratio in quadrant analysis of the Seohan computerized hue test.
  
  
  RESULTS
  The Seohan computerized hue test showed that the sum of Q2+Q4 was significantly higher than the sum of Q1+Q3 in congenital color vision deficiency (P<0.01, paired t test) and that the sum of Q2+Q4 was significantly lower than the sum of Q1+Q3 in acquired color vision deficiency (P<0.01, paired t test). In terms of discriminating congenital and acquired color vision deficiency, the ratio in quadrant analysis had 93.3% sensitivity and 98.5% specificity with a reference value of 1.5 by the Seohan computerized hue test (95% confidence interval).
  
  
  CONCLUSIONS
  The quadrant analysis and ratio of (Q2+Q4)/(Q1+Q3) using the Seohan computerized hue test effectively differentiated congenital and acquired color vision deficiency.
authors.affiliation: Department of Ophthalmology, Dongguk University College of Medicine, Dongguk University International Hospital, Dongguk, South Korea.
authors.forename: Young Joo
authors.initials: YJ
authors.lastname: Shin
authors.forename: Kyu Hyung
authors.initials: KH
authors.lastname: Park
authors.forename: Jeong-Min
authors.initials: JM
authors.lastname: Hwang
authors.forename: Won Ryang
authors.initials: WR
authors.lastname: Wee
authors.forename: Jin Hak
authors.initials: JH
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003119:Color Perception Tests / Q000592:standards*; D003117:Color Vision Defects / Q000151:congenital* / Q000175:diagnosis* / Q000209:etiology; D003430:Cross-Sectional Studies; D003936:Diagnosis, Computer-Assisted / Q000592:standards*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged