title: A method for identifying color vision deficiency malingering.
abstract: OBJECTIVE
  To propose a new test to identify color vision deficiency malingering.
  
  
  METHODS
  An online survey was distributed to 130 truly color vision deficient participants and 160 participants willing to simulate color vision deficiency. The survey contained three sets of six color-adjusted versions of the standard Ishihara color plates each, as well as one set of six control plates. The plates that best discriminated both participant groups were selected for a "balanced" test emphasizing both sensitivity and specificity. A "specific" test that prioritized high specificity was also created by selecting from these plates. Statistical measures of the test (sensitivity, specificity, and Youden index) were assessed at each possible cut-off threshold, and a receiver operating characteristic (ROC) function with its area under the curve (AUC) charted.
  
  
  RESULTS
  The redshift plate set was identified as having the highest difference of means between groups (-58%, CI: -64 to -52%), as well as the widest gap between group modes. Statistical measures of the "balanced" test show an optimal cut-off of at least two incorrectly identified plates to suggest malingering (Youden index: 0.773, sensitivity: 83.3%, specificity: 94.0%, AUC of ROC 0.918). The "specific" test was able to identify color vision deficiency simulators with a specificity of 100% when using a cut-off of at least two incorrectly identified plates (Youden index 0.599, sensitivity 59.9%, specificity 100%, AUC of ROC 0.881).
  
  
  CONCLUSIONS
  Our proposed test for identifying color vision deficiency malingering demonstrates a high degree of reliability with AUCs of 0.918 and 0.881 for the "balanced" and "specific" tests, respectively. A cut-off threshold of at least two missed plates on the "specific" test was able to identify color vision deficiency simulators with 100% specificity.
authors.affiliation: Yale Department of Ophthalmology & Visual Science, Temple Medical Center, 3rd Floor 40 Temple St., New Haven, CT, 06510, USA. andrew.pouw@yale.edu.
authors.forename: Andrew
authors.identifier: http://orcid.org/0000-0001-8594-7612
authors.initials: A
authors.lastname: Pouw
authors.affiliation: Doheny Eye Institute, University of California Los Angeles, Los Angeles, CA, 90031, USA.
authors.forename: Rustum
authors.initials: R
authors.lastname: Karanjia
authors.affiliation: Doheny Eye Institute, University of California Los Angeles, Los Angeles, CA, 90031, USA.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Sadun
mesh_terms: D000328:Adult; D003118:Color Perception / Q000502:physiology*; D003119:Color Perception Tests / Q000379:methods*; D003117:Color Vision Defects / Q000175:diagnosis* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008306:Malingering / Q000175:diagnosis* / Q000503:physiopathology; D012372:ROC Curve; D015351:Vision Screening / Q000379:methods*
keywords: Color blindness; Color vision deficiency; Diagnostic tests; Malingering; Pseudo-isochromatic plates; Psychophysics