Prevalence of malingering in patients with chronic pain referred for psychologic evaluation in a medico-legal context.

OBJECTIVE

To provide an empirical estimate of the prevalence of malingered disability in patients with chronic pain who have financial incentive to appear disabled.

DESIGN

Retrospective review of cases.

SETTING

A private neuropsychologic clinic in a southeastern metropolitan area.

PARTICIPANTS

Consecutive patients (N=508) referred for psychologic evaluation related to chronic pain over a 10-year period (1995-2005).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Prevalence of malingering was examined using 2 published clinical diagnostic systems (Malingered Pain-Related Disability and Malingered Neurocognitive Dysfunction) as well as statistical estimates based on well validated indicators of malingering.

RESULTS

The prevalence of malingering in patients with chronic pain with financial incentive is between 20% and 50% depending on the diagnostic system used and the statistical model's underlying assumptions. Some factors associated with the medico-legal context such as the jurisdiction of a workers' compensation claim or attorney representation were associated with slightly higher malingering rates.

CONCLUSIONS

Malingering is present in a sizable minority of patients with pain seen for potentially compensable injuries. However, not all excess pain-related disability is a result of malingering. It is important not to diagnose malingering reflexively on the basis of limited or unreliable findings. A diagnosis of malingering should be explicitly based on a formal diagnostic system.