title: A novel test to differentiate anosmic malingerers from actually anosmic patients.
abstract: BACKGROUND
  The available olfactory evaluation tests are mainly subjective methods requiring patients' collaboration. If, for any reason, the patients refuse to honestly report what they perceive, the test reliability will be questionable; this condition is potentially observable  in malingering patients because of their financial or psychosocial incentives. In an olfactory discrimination test context, this study was aimed to design a test capable of distinguishing malingerer from actually anosmic or severely hyposmic patients.
  
  
  METHODS
  The pilot  experiment of our methodology study determined five substances (coffee, lemon, rosewater, thyme, and garlic) as qualified odors of a 20-item odor discrimination test and set its normal reference value at 15. Through two simulations, 70 normosmic participants emulated actual anosmia and also  malingering. The outcome results were used to measure test reliability factors.
  
  
  RESULTS
  During the malingering simulation, only seven participants were capable of keeping their scores at the test chance level with enough randomness in their sequences of answers while the  actual anosmia simulation revealed that 39 had scores at the test chance level. Accordingly, the Tehran University Odor Discrimination Test (TUODT) was measured to have 90% sensitivity, 55.71% specificity, 67.02% positive predictive value, and 84.78%negative predictive value.
  
  
  CONCLUSIONS
  The TUODT is a relatively efficient method to identify anosmia malingerers.
authors.affiliation: Department of Otolaryngology, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Jalal
authors.initials: J
authors.lastname: Mehdizade
authors.forename: Babak
authors.initials: B
authors.lastname: Saedi
authors.forename: Reza
authors.initials: R
authors.lastname: Fotouhi
authors.forename: Amin
authors.initials: A
authors.lastname: Safavi
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008306:Malingering / Q000175:diagnosis*; D008875:Middle Aged; D009812:Odorants; D000857:Olfaction Disorders / Q000175:diagnosis*