http://en.wikipedia.org/wiki/United_States_v._Binion
"Third, the issue of malingering is particularly problematic as there is no ultimate test, and such diagnoses boil down to clinical decisions. An extensive review of the literature by Melton et al did not reveal any studies in which clinicians using various combinations of testing procedures and interviews demonstrated any "extraordinary ability" to detect malingering.[5]
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http://en.wikipedia.org/wiki/Malingering
Malingering
Malingering is a medical and psychological term that refers to an individual fabricating or exaggerating the symptoms of mental or physical disorders for a variety of motives, including getting financial compensation (often tied to fraud), avoiding work, obtaining drugs, getting lighter criminal sentences, trying to get out of going to school, or simply to attract attention or sympathy. Because malingerers are usually seeking some sort of primary or secondary gain, this disorder remains separate from Somatization disorders and factitious disorders in which the gain is not obvious. Legally, malingering is often referred to as Fabricated mental illness or Feigned mental illness. See United States v. Binion.[1]
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