One of the earliest known texts on faking psychiatric illness was written by Isaac Ray in 1838 and played an important role in the M'Naghten case (and the insanity standard that arose as a result). Mental health professionals also became aware of the different motivations behind attempts at faking. Malingered psychiatric illness tended to be rare when most mental patients were forced into asylums from which they had little chance of leaving. If it happened at all, it was in forensic cases with offenders trying to avoid prison or execution. Only in the past several decades, with changes in health care, newer diagnoses and increased financial compensation for emotional problems, has malingered psychiatric cases become more common.
There is no way to give justice to the forms that psychiatric malingering can take. Clinical diagnoses including post-traumatic stress disorder, mood disorders,adjustment disorders and postconcussional syndrome tend to be more associated with potential malingering due to the subtle nature of the symptoms involved. Although there is an extensive literature on testing for malingering and a range of psychometric tests that can be applied to investigate the possibility of faking, making a definite diagnosis of malingering is still extremely difficult for professionals.
While personality disorders (especially antisocial personality disorder and psychopathy) have traditionally been associated with malingering, chronic psychopaths do not appear to be all that successful at faking symptoms. Studies of malingering in forensic populations have not shown any strong link although patients diagnosed with personality disorders are often accused of malingering when they present unusual symptoms or request potentially addictive medication.
Faking psychiatric symptoms to avoid a long prison sentence or even to solicit medication still goes on. Clinicians doing forensic assessments for patients awaiting trial often have trouble reconstructing the events leading up to the crime for which the patient is being charged. Were there any signs leading up to the episode in question? Did the patient have a psychiatric history prior to the offense? Suspicions arise when there is little or no evidence that psychiatric problems actually existed before the (typically violent) offense occurred. Hallucinations, delusions and other symptoms need to be carefully evaluated to rule out potential faking.
In his classic work on deception, Richard Rogers proposed a threshold model for consideration of malingering. Psychological or physical symptoms associated with malingering include: suspicion of voluntary control over symptoms, atypical presentation in the presence of external incentives, atypical presentation in the presence of undesirable external conditions (do the symptoms get worse when the patient is being forced to do something undesirable?), complaints that are inconsistent with actual clinical findings, and substantial noncompliance with evaluation or treatment.
Psychometric approaches to malingering tend to focus on identifying atypical symptoms that are unlikely to appear in actual cases. Most personality inventories include faking scales designed to catch potential fakers although there is some controversy concerning their value. Other approaches involve comparing subtle versus obvious symptom responding to determine deliberate faking. Most clinicians tend to combine multiple detection strategies to ensure that their assessments are as accurate as possible.
There is also an important distinction that needs to be made between symptom exaggeration and true malingering, (is the patient inventing the symptoms completely or exaggerating symptoms that he/she is actually experiencing?) While many clinicians (including myself) views this as a fundamental distinction that needs to be made in clinical diagnosis, other clinicians (and insurance companies) do not.
Another important issue involves the implications of a malingering diagnosis - regardless of whether it is deserved. Once the malingering label is attached to a patient's case, the backlash can be extreme in forensic and compensation cases. For that reason, assessment professionals need to be particularly cautious in making a malingering diagnosis including full documentation of available evidence and ruling out all other possible diagnoses.
While malingering is hardly rare in most medical settings, clinicians have a tendency to downplay its significance considering the potential pitfalls in accusing patients of inventing or exaggerating symptoms. The true incidence of malingering will always be unknown (only the unsuccessful malingerers will ever be caught) but the long war between the malingerer and the assessment professional goes on.