SUMMARY: There are no reliable criteria on which to judge how commonly malingering of chronic benign pain occurs. There are no valid tests of malingering in chronic benign pain, but psychological evaluation can assist by making or excluding alternative diagnoses.
Though it is a frequent concern of personal injury litigators, malingering of chronic pain has rarely been systematically researched 1.
Despite recent suggestions that awareness is not either present or absent but a matter of degree, the conventional distinction is between aware malingering and unaware somatisation.
There are no reliable criteria on which to judge how commonly malingering of chronic benign pain occurs. As previously discussed, the terminology functional overlay has no validity and should be abandoned. Similarly, Symptom Amplification Syndrome is a concept for which there is no acceptable scientific support.
Pain Disorder is a variety of Somatoform Disorder, for which there are generally accepted, defined criteria, as there are for Malingering, in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition [DSM-IV].
There are no valid tests of malingering in chronic benign pain, but psychological evaluation can assist by making or excluding alternative diagnoses. DSM-IV Criterion C for Pain Disorder is the central distinguishing feature for which psychiatric or psychological expertise is required:
Psychological factors are judged to play a significant role in the onset, severity, exacerbation, or maintenance of the pain.
Both claimant and defence counsel should insist that Pain Disorder and Somatoform Disorder be substituted for the ill-defined and often pejorative terms that physical medicine specialists sometimes use in expert reports and testimony.
For litigation purposes, it is useful to classify 2 claimants' intentional deception:
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PRACTICE POINT Types of Malingering
1. Pure (feigning disease, disability) 2. Positive (feigning symptoms) 3. Partial (conscious exaggeration) 4. False imputation of cause 5. Dissimulation (concealment) 6. Continuance (already gone) |
Recent meta-analysis 3 suggests that some chronic pain patients are malingering, but the poor quality of the available studies makes the quoted prevalence figures of 1-10% unreliable.
A 40 year-old study 4, 5 on "cure by verdict" is a medicolegal classic. Even if Miller's 1961 findings had been confirmed by subsequent studies - which they were not 6 - the prevalence of malingering would be only 1.25%.
Various methods of testing for malingering have been proposed but found not to be valid:
Only isokinetic strength testing has promise among the methods currently available. The speed of muscle contraction is kept constant but there is a variable resistance that adjusts to the muscle's ability to generate force. The research to date is consistent that the test can distinguish between maximum and submaximal effort, and between a best and a faking effort.
It remains unclear why isokinetic strength testing appears to discriminate where isometric (constant muscle length) fails.Copyright © 2008 Electronic Handbook of Legal Medicine