Update Article
The Hong Kong Practitioner VOLUME 25 / July 2003

The interesting phenomenon of malingering
K Y Mak 麥基恩

Summary

Lying is a common human behaviour, and the tendency to modify or edit past memories in pursuit of present needs is universal. However, it can become an important issue in clinical and forensic medicine. Doctors should be on the look out for malingering during clinical practice, but should not overlook genuine psychiatric disorders that need prompt management. There are various clinical clues and diagnostic instruments to help doctors in handling patients who exaggerate or feign physical or mental disorders, but no test is foolproof. A comprehensive and multi-disciplinary approach is sometimes needed.

摘要

說謊是人類常見的行為，傾向於修改過往的記憶來達到現在的需要。但這在臨床和法醫學上會成為重要的問題。醫生必須分辨出詐病的病人，同時又不要漏診及真實的精神病者，因為他們需要及時的醫療。現在已有很多臨床提示和診斷工具可以幫助醫生找出誇大病症或者是虛假的生理或精神疾病的情況，但並非有百份百保證。有時需要採用全面性、多學科結合的方式處理。

HK Pract 2003;25:325-332


K Y Mak, MBBS(HK), MD(HK), DPM, FRCPsych
Honorary Professor,
Department of Psychiatry, The University of Hong Kong.

Correspondence to :
Dr K Y Mak,
Department of Psychiatry, The University of Hong Kong, Queen Mary Hospital, Hong Kong.


Introduction

Lies, deceptions, and false beliefs are universal. College students used to make an average of two lies per day.1 In the early chapters of the Bible, Adam and Eve lied to God. In everyday life, people talk about "white lie" and "black lie". The former has good intention to protect the feelings of others e.g. appreciating an unwanted gift, while the latter is just frank deception. Magicians have always deceived us by their apparent self-injurious behaviours such as swallowing the sword, amputating part of the body, etc. Medical history is full of stories about people who lied telling of imaginary illnesses or who feigned illness in order to get hospitalisation and treatment including disfiguring surgery.2

Before discussing the psychopathology of lying, there are certain terms that need to be clarified, namely:

-
Malingering: faking or exaggeration of physical or psychological symptoms for external gain.
-
Factitious disorders: faking or exaggeration for pleasure from being sick (playing the sick-role).
-
Conversion disorders: faking or exaggeration without a conscious awareness of the purpose.
-
Somatoform disorders: repeated presentation of physical symptoms without physical basis.
-
Similation (illness illusion): symptoms completely feigned.
-
Dissimulation: minimisation of real symptoms.
-
Illness enhancement: magnification of real symptoms.
-
False imputation: real symptoms falsely attributed to other reasons.



Developmental approach

It is said that very young children (<3 years) cannot distinguish false beliefs from overt lies.3 Children learn or even are taught lying from their parents and others to gain self-benefits or avoid punishment e.g. not attending school. Achenbach4 estimated that 23% of kids aged four to five years lie and cheat. The percentage then declined to 15% in the 16 year-old adolescents. Later, there is an increase in lying that is also associated with anti-social behaviour.

Adults lie and deceive for a purpose, usually for money such as public assistance. Occasionally, there is some good-intentioned lying, called retrospective falsification often appears during funerals e.g. giving of exaggerated honours towards the deceased person. Finally, towards the evening of life, in the elderly, there is a special form of lying called confabulation, a compensation for their memory loss which happens in dementia and other brain diseases.


Clinical scenarios

As lying is so common, when does it become abnormal or pathological? There are certain situations in which intentional lying should be distinguished from the unintentional.

In clinical practice, it is important to assess whether or not the person is suffering from a psychiatric disorder, when the patient presents with physical or psychological symptoms that are not consistent with the circumstances or physical findings from clinical examination or laboratory results. This is important as a wrong diagnosis can lead to wrong treatment, and more severe underlying psychopathologies may be missed. Yates et al found 13% of patients attending the Accident & Emergency Department are suspected of malingering. Roger et al found a 15% prevalence.

In medico-legal cases, feigning of physical disease is common for civil compensation. Feigning of mental illness may be of particular great importance if there are potential penal consequences, especially if there is the possibility of avoiding a severe punishment or even facing the death penalty (through the verdict of guilty but insane).

There are also certain situations in which the testimonies have to be contested. An example is that of false allegations by the victims as in rape cases, the so-called false memory syndrome. In child abuse (physical or sexual) the history from memory provided by the victim may not be reliable, and the capacity of child witnesses to testify accurately is often called into question. Such situations are important not only because justice cannot be carried out but it would also be very costly to individuals and to society.


Types of malingering

Rogers et al6 proposed four types of malingering, namely:

  1. Rare symptoms endorsement: attitudes, problems and self-reported symptoms that are very infrequent among patients e.g. strange smells;

  2. Indiscriminate symptom endorsement: a strategy to adopt that the more symptoms there are, the more likely they will be considered as being sick e.g. saying "yes" to all suggested symptoms;

  3. Blatant symptoms endorsement: a high frequency of clear and obvious symptoms of psychopathology e.g. auditory hallucinations, suicidal thoughts, etc; and

  4. Improbable symptom endorsement: claiming the presence of absurd and never reported symptoms even in the truly disturbed patients e.g. head fallen off the body.


Aetiology

Regarding socio-demographic variables, there is no conclusive evidence concerning the gender, economic status or race of the person. On the whole, the I.Q.s of the malingerers are usually higher than the average person, and some are fairly successful and skilled e.g. in the control of facial expression. On the other hand, their moral reasoning (for justice, fairness, personal worth, etc.) and religious beliefs (that lying is sinful) are usually lower than others.2

The exact aetiology of malingering is not definite, but is often the result of a number of bio-psycho-social factors. It has been said that parental modeling is important in the shaping of malingerers. According to the DSM-IV definition for malingering, the condition is the intentional production of false or grossly exaggerated physical or psychological symptoms, motivated by external incentives such as avoiding military duty or work, obtaining financial compensation, evading criminal prosecution or obtaining drugs.5 It is often associated with an anti-social personality disorder.


Motivation for deceiving

According to Pankratz,2 there are some behavioural theories that drive patients to deceive, namely:
 
1.

Abnormal illness behaviour: which is the inappropriate or maladaptive mode of experiencing, perceiving, evaluating or responding to one's own state of health, and the focus might be the symptom, the ideas or the behaviour.6
 
2.

Hospital addiction and substance abuse: these patients can solicit medications through repeated hospitalisation.

 
3.

Sensation seeking: some patients obtain repeated thrills and excitement through the procedures of hospital care.
 
4.

Fantasy-prone patients: Wilson and Barber7 described them as "psychosomatically plastic" patients, as they tried to experience their fantasies in reality.

 

Resnick1 broadly classify the underlying motives into either internal or external categories:

 
 

Internal or psychological motives

  -

attention seeking;

  -

sympathy and favouritism seeking;

 
  External or social motives
  - judged not competent to stand trial;
  - leniency in sentencing;
  - to avoid military service;
  - easier life in prison;
  - hospital care (those who are single and homeless who claim they are suicidal);
  - financial gains (those seeking compensation).


Differential diagnoses

Not all persons who lie are malingerers. Many are suffering from genuine psychiatric disorders which are described in more details below:

  1. Factitious disorders9 - the intentional production or feigning of physical or psychological signs or symptoms, the motivation of which is to assume the sick role. The most famous type is the Munchausen's Syndrome8 that was based on a favourite story-book character described by Rudolph Raspe in "The Singular Adventures of Baron Munchausen". This fictional baron wandered widely and told untruthful theatrical stories, with the psychological need to assume the sick-role. There were originally three subtypes: acute abdominal, haemorrhagic and neurological, and others were subsequently added. Many synonyms were created e.g. the hospital addiction syndrome, Van Gogh syndrome, artifactual illness, etc.2 The syndrome can be personal, or by proxy if deliberately inflicted on another, such as a child.

  2. Somatoform disorders9 - including conversion disorder and psychogenic pain syndrome. For conversion disorder, there are one or more symptoms or deficits affecting voluntary motor or sensory function that suggest a neurological or other general medical condition, and psychological factors are judged to be associated. For psychogenic pain syndrome, the pain is the predominant focus and is of sufficient severity to warrant clinical intention with significant distress or impairment in functioning. Psychological factors are judged to have an important role in the onset, severity, exacerbation or maintenance of the pain. In both conditions, the symptoms are not intentionally produced or feigned.

  3. Dissociative disorders9 - there is a disruption in the usually integrated functions of consciousness, memory, identity, or perception of the environment. The more notorious subtypes are the Dissociative Amnesia and the Ganser Syndrome. Dissociative Amnesia is characterised by an inability to recall important personal information, usually of a traumatic or stressful nature, that is too extensive to be explained by ordinary forgetfulness. The Ganser syndrome (previously known as prison psychosis) was formerly classified as a hysterical conversion and was typified by the giving of approximate answers to questions e.g. "2 plus 2 equals 5" or "a table has three legs". There is one more subtype that used to be very popular, that of multiple personality disorder with its famous "three faces of Eve" story which at one time had grown into epidemic proportion in the U.S.A.

  4. Post-traumatic stress disorder9 - the patient has been exposed to a traumatic event that involved actual or threatened death or serious injury, or a threat to the physical integrity of self or others, and the person's response involved intense fear, helplessness or horror. The traumatic event is persistently re-experienced with persistent symptoms of increased arousal, together with persistent avoidance of stimuli associated with the trauma.

  5. Post-concussional or post-traumatic brain syndrome9 - the syndrome occurs following head trauma and includes a number of disparate symptoms such as headache, dizziness, fatigue, irritability, difficulty in concentrating and performing mental tasks, impairment of memory, insomnia, and reduced tolerance to stress, emotional excitement, or alcohol.

It has often been alleged that Ganser syndrome10 is a sign of those who feign mental illness, but it can occur in psychotic patients (sometimes called hysterical psychosis) and organic dysphasias. Because the symptoms in both post-traumatic stress disorder and post-concussional syndrome are not definite, they can easily be feigned and thus often not believed, especially in view of the compensation issue. Even genuine patients may feel it necessary to exaggerate their claims in order to impress others.1 One should therefore look for other more specific symptoms e.g. intolerance of loud noise or bright lights; and to ask sleeping partners about patients' sleep pattern (disarrayed bed covers, waking up in fear at midnight, etc).



Clinical assessment

There are at least three areas that need serious attention:

 
1.

The intention or motivation,

2.

The context or setting and

3. The expectation from the recipient.11

 

However, even detectives, police officers and customs officers (with the exception of perhaps the Secret Service) are sometimes no better at ascertaining lies than college students.1 Doctors and psychiatrists are no exception, but there are sometimes cues that prompt the clinicians of the possibility of malingering.

 
A.

Clinical history taking

This should be open and flexible. The patient's emotional state and attitudinal or belief systems can affect his presentation of symptoms and response to questions. Subtle brain damage and the side-effects of drugs are influencing factors. Then there are patients who try hard to please their clinicians by giving answers they think their clinicians want; and some patients even give distorted answers when they find their clinicians not listening or taking their problems seriously.2

Basically, there are three main areas of exploration during history taking:

 
 

a.
Individual account - During the history taking, there are certain points that have to be looked for:
   
 
i.
Voluntary veracity: too willing to share without being asked, protestations and over-acting, in contrast to true patients who often hide their symptoms;
     
   
ii.
Unusual symptoms e.g. experiencing hallucinations while talking to interviewer without any sign of distraction or atypical symptoms e.g. visual hallucination in schizophrenia without auditory form, continuous voices rather than intermittent, sudden onset and termination of symptoms, etc.
     
   
iii.
Inconsistencies between observed and reported accounts and inconsistencies between observed symptoms at different times or with different persons;
     
   
iv.
Lack of measures to counteract the symptoms e.g. passive obedience of all command hallucinations, no hiding or pulling down the shades to avoid the paranoid delusion of being watched, etc;
   
 
b.
The context - Understanding the psychiatric phenomenon within the contextual environment e.g. a murder without robbing a stranger should raise the possibility of a genuine psychiatric disorder.
   
 

c.

 

The historical data - Previous history and past behaviour are valuable guides. For example, mental retardation can be easily verified by past school records and work experience. Persons with stable jobs are less likely to fake than persons who change jobs frequently. Collateral information from other sources such as the police reports, hospital records, ward staff reports, etc. are often informative.

 
B.

Mental state examination

A semi-structured or a structured interview is more reliable than unstructured examination. There are a few schedules that can assist the doctor in doing a more complete assessment, and the most commonly used tools are:

   
  1.
The Structured Interview of Reported Symptoms (SIRS)12
This measure of feigning is of high validity and consistency. There are 7 primary scales and 5 supplementary scales.
     
  2.
The Psychopathy Check-list - Revised13,14
This is of high reliability especially for those with severe personality disorders, but of uncertain validity. This instrument is quite time-consuming with 8 scales for factor I, and 9 scales for factor II and the cut-off score is 30 or more.
     
 

It is found that the results are more accurate if the questions are asked in rapid-fire fashion, so as to rob the person of time to think up consistent answers.

During the examination, the doctor should be aware of the following:

   
  i.
Facial expression: least reliable because since early in life one learns not to show expressions that reveal real feelings; inexperienced personnel sometimes deduce false assumptions or imputation from this area. A common mistake in detecting lies is the belief that a liar cannot look others in the face and lie.
     
  ii.
Clues: they tend to speak at a higher pitch, are hesitant in answering questions, make grammatical errors, use the passive voice, make slips of tongue.
     
  iii.
More negative, evasive, over-generalised or irrelevant statements in response to questions (but over-inclusive statements in narrative accounts suggest truth).
     
  iv.
Self-manipulating gestures e.g. rubbing, scratching; inconsistencies between verbal and non-verbal communications (e.g. sincerity of face vs evidence of anxiety in other parts of the body); sound like a rehearsal.
     
  v.
Easy acceptance and take on other unrelated psychiatric symptoms when suggested to them or overheard e.g. defects in drawing for schizophrenia.
     
  vi.
Manic signs e.g. pressure of speech, flight of ideas and loosened associations are difficult to feign; depressive features however are easy to fake, but not the knowledge of diurnal variation and early morning insomnia.
     
 
A few points here are worth noting and knowing:
     
  -
Powell1 called on psychiatric staff to fake schizophrenia. The staff markedly exaggerated the cognitive deficits compared to true patients, were more likely to draw attention to the delusion symptoms, had very dramatic hallucinations and gave approximate answers.
     
  -
Malingerers dislike lengthened interviews. They sometimes challenge the examiners about their doubts (e.g. "You don't believe in me, do you?") in order to shorten the time. They also dislike being tested or having treatment. On the other hand, patients with factitious disorder and especially those with conversion disorder are eager to be examined and treated.
     
  -
Some people are good liars: actors, those who exaggerate, those who are imaginative, have good memory, are charismatic, and the extroverts (compared to introverts). Those who are in contact with mental patients, and those who have genuine past psychiatric disorders are the best malingerers.
 
  -
It is easier to detect feigned psychosis than feigned cognitive deficits. Those feigning the former can be asked to elaborate, while the latter can just give "I don't know" as answers.1 Anderson15 found feigners did not fake well with symptoms of psychosis and depression, and they would not choose perseveration in contrast to truly ill patients. Fatigue during long interviews often decreases the ability to fake. Fakers consistently gave approximate answers.
 
  -

Pankratz2 warned that clinicians, improperly influenced by others and those with narrow schemas or infatuated with a fad (such as a recent paper on malingering), may prematurely eliminate alternative hypotheses other than malingering.

 
C.

Diagnostic tests

To those interested in the disorder, and those with legal responsibilities in detecting the malingerer, the following psychometric instruments can be useful to test the truthfulness of the answers:

     
  -
The MMPI-2 F (Infrequency)-minus-K (Defensiveness) index and scale F(p) - to identify malingerers;16,17 the Lie (L) scale though helpful is not actually a measure of lying tendencies.
     
  -
The MACI personality inventory (more emphasis on psychopathology) - the Modifier Indices with 4 subscales measuring self-report styles of Reliability, Disclosure, Desirability and Debasement each with its set of questions.
     
  -
Rorschach test - results may help detect denial by positive impression or detect malingering by negative impression.19 However, doing this test can be faked, though more difficult if Exner's scoring system is used.
     
  -
Statement reality analysis,20,21 - a semi-objective examination of verbal or written statements, based on the assumption that reputable persons can lie and persons of questionable character can tell the truth, thus the importance of the recorded statements. Gudjonsson22 cited the criteria as originality, clarity, vividness, internal consistency, detailed specific descriptions, specific details, subjective feelings, spontaneous corrections or additional information, but these criteria are criticised for lack of precision or definition. Steller & Koehnken23 modified the criteria into 5 dimensions: general characteristics, specific contents, peculiarities of contents, motivation-related contents, and offense-specific elements; but Bekerian & Dennett24 found that the motivation-related criterion was not useful.
     
  Rogers25 et al identified six strategies to detect potential malingering:
     
  1.
Floor effect - even severely impaired individuals can succeed
     
  2.
Performance curve - genuine patients will reach a level and then fail more difficult items
     
  3.
Magnitude of error - approximate but inaccurate or grossly wrong answers by malingerers
     
  4.
Symptom validity testing - genuine deficit patients expected to have a 50% error rate by chance in selecting two alternatives, while malingerers have extreme high error rate
     
  5.
Atypical presentation - evidence of inconsistent performance across repeated testings
     
  6.

Psychological sequelae - malingerers report an unusually high number of psychological symptoms.

 
D.

Specific neuro-psychological or cognitive tests

With the assistance from a psychologist or an expert in neuro-psychology, the following additional tests can be employed, namely:

     
  -
Examine the structure of language used (e.g. pauses, references to self, connecting words like "next", "after", etc).
     
  -
Cognitive tests e.g. the Luria Nebraska Neuro-psychological Battery,26 the Bender Visual-Motor Gestalt Test,27 the Wechsler Adult Intelligence Scale-Revised in which the Digit Span is particularly affected.28
     
  -

Rey's 15-item memory test: malingerers score much worse than brain-injured patients as they exaggerate the deficits.

 
E. Other methods
     
  a.
Hypnosis and abreaction with medication like sodium amytal was previously quite popular, but this was found not useful as persons can maintain their lies while hypnotised.
     
  b.
Lie machines (polygraphs including electro-encephalography) are 80-90% accurate. Even so, 50% of trained subjects can produce false negative results. Furthermore, they are often not admissible in courts.
     
  c.
In case of civil litigations, detectives are sometimes employed and the behaviour of the victims is sometimes videotaped.


Management

Once feigned mental disorder is suspected, the doctor should be careful in handling the patient, especially if the probability of a factitious disorder is high on the list. When confronting the patient without taking a punitive attitude, some face-saving procedures can be adopted in order to avoid a possible adverse reaction (such as aggressive behaviour) from the patient. Generally speaking, open challenge to the patient as regard the feigning of illness has no therapeutic effect; instead it drives the patient to other doctors for treatment. Besides, the labeling of malingering could have other adverse consequences, including that of giving inappropriate treatment.

Malingering is strictly speaking not a psychiatric disorder. However, it should be noted that even for malingerers lying in one area does not necessarily mean that the person's mental illness is totally feigned; and not all who feign are without any need for help. Some do have pervasive psychopathologies that need treatment.

The most appropriate strategy to employ is the problem-orientated approach, with emphasis on psychological and social difficulties. Discussion with the patient (and other involved persons) is important to enable a management plan to be set up, with the aim to help patient face the underlying cause in a more realistic and socially acceptable way. Sometimes, referral to a clinical psychologist or an occupational therapist for further assessment is useful, and expert legal advice especially on the issues of confidentiality (such as disclosure to other parties) and invasion of personal privacy (such as searching the patient's properties or surveillance by videotaping) should not be overlooked. In case of uncertainties, admission to hospital for a certain period with careful observation by staff may be useful.

Stress management techniques as well as social skills training programmes can be recommended. Sick-leave certificates should not be lightly given, and the use of medications for symptomatic treatment should be cautious after balancing the various risks and the benefits in such a maneuver.


Conclusion

Doctors, even experienced ones, are not perfect in detecting malingering. Rosenhan29 concluded that mental health professionals are not good in distinguishing genuine from faked mental illness. Research suggested that circumscribed amnesia (not global amnesia which is really rare) is most difficult to distinguish, even by clinicians.1 No method is foolproof, and there is no perfect test. Even doing neuro-psychological tests can be faked, and Heaton found such tests are only 20% better than chance in detecting fake.6

Doctors should also avoid their personal bias in distinguishing malingering from other psychiatric problems, especially when they have been "cheated" by malingerers before. False imputation by doctors can cause similar serious harms as similation. Comprehensive or multi-faceted evaluation is usually needed, and completeness of collateral information is important, perhaps backed up by objective testings. On occasions, professionals from other disciplines such as clinical psychologists and occupational therapists can be of assistance.



Key messages

  1. People who appear to feign their illness have various reasons.

  2. Those who do so for personal gains or to avoid loss are called malingerers and they do not have any formal psychiatric disorder.

  3. Those who feign because of a strong sick-role tendency have the psychiatric factitious disorder.

  4. Others presenting with imaginary illnesses but without the intention to feign may be suffering from genuine psychiatric disorder such as dissociative disorder or somatoform disorder.

  5. The differentiation can be of great importance when providing expert opinion in forensic medicine.

  6. Doctors should be aware of malingerers during clinical practice, but should not overlook genuine psychiatric disorders that needs prompt management.

  7. A multi-disciplinary team is sometimes needed to tackle the issue.


References

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