Pain, malingering and the WAIS-III Working Memory Index.
BACKGROUND
Pain patients often report cognitive symptoms, and many will include them in their claims of disability. There is empirical evidence that patients with pain do experience problems on attention-demanding cognitive tasks, but the results are mixed and the potential impact of exaggeration in the context of pain-related litigation has not been addressed.


OBJECTIVE
1) Examine the impact of pain and malingering on attention; 2) determine if the Working Memory Index (WMI) of the Wechsler Adult Intelligence Scale-3 (WAIS-III) can reliably detect malingering.


METHODS
Study 1: simulator design; Study 2: clinical known-groups design.


METHODS
Study 1 used healthy college students; Study 2 used chronic pain patients and neurological patients.


METHODS
The WMI and its constituent subtests.


METHODS
Study 1: College students were administered the WMI under three conditions: standard administration, with cold-pressor induced pain, or with instructions to simulate impairment due to pain. Study 2: Known-groups design in which the WMI was examined in non-malingering and definite malingering chronic pain patients, non-malingering moderate-severe traumatic brain injury, and memory disorder patients seen for routine psychological evaluation. Malingering was operationalized using published criteria.


RESULTS
There were no group differences in WMI or its subtests among non-malingering groups, but some individual clinical patients with pain did score at a level suggestive of attentional impairment. The lowest scores were found in the simulated malingering college students and definite malingering clinical pain groups, in which about half scored worse than 95% of the non-malingering clinical patients.


CONCLUSIONS
This study demonstrated that even when controlling for exaggeration some pain patients do exhibit problems with attentional function. However, significant impairment in WMI performance (eg, index score<or=70), particularly in the absence of brain dysfunction, cannot reasonably be attributed to the effects of either acute or chronic pain, even at moderate to severe levels, and likely reflects intentional exaggeration.
Etherton
Joseph L
JL
Department of Psychology, Loyola University, 6363 St. Charles Avenue, New Orleans, Louisiana 70118, USA.
Bianchini
Kevin J
KJ
Ciota
Megan A
MA
Heinly
Matthew T
MT
Greve
Kevin W
KW
D000223:Adaptation, Psychological; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002908:Chronic Disease; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000175:diagnosis* / Q000453:epidemiology; D008875:Middle Aged; D009483:Neuropsychological Tests; D010146:Pain / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology*; D015995:Prevalence; D011336:Probability; D011379:Prognosis; D012016:Reference Values; D015203:Reproducibility of Results; D018570:Risk Assessment; D012720:Severity of Illness Index; D012737:Sex Factors; D018434:Sickness Impact Profile; D014888:Wechsler Scales