Can posturography identify informed malingerers?
OBJECTIVE
This study evaluated whether information about computed dynamic posturography given to subjects instructed to feign vestibular impairment (malingerers) improved their attempts to display test patterns consistent with vestibular weakness.


METHODS
The study design was prospective, with blinded scoring of tests.


METHODS
The study was conducted at a university hospital.


METHODS
Sixty volunteer subjects, 20 to 59 years old, were randomly assigned to one of two equal groups: naïve subjects and subjects informed about computed dynamic posturography.


METHODS
Computed dynamic posturography was performed twice. First, subjects were instructed to feign a vestibular weakness. Second, subjects were instructed to perform the test normally. One group was given additional information about computed dynamic posturography before the first test (informed faking).


METHODS
The computed dynamic posturography test summaries were scored as normal, aphysiologic, or vestibular by two methods: the scoring method published by Cevette et al. in 1995 and blinded clinical scoring. The computed dynamic posturography test summaries of patients referred for vestibular disorders were included with the test summaries collected from subjects during scoring. These additional tests of possible "true" vestibular disorder allowed evaluation of scoring accuracy.


RESULTS
The scoring method of Cevette et al. classified about one-third of the test results of feigned vestibular weakness as either normal (16.7%) or vestibular weakness (18.3%). The remaining two thirds of the test results of feigned vestibular weakness were classified as aphysiologic (65.0%). Blinded clinical scoring gave similar figures. Additional information about computed dynamic posturography did not increase the number of feigned test results scored as a vestibular weakness.


CONCLUSIONS
When additional information about computed dynamic posturography was provided, the subjects did not improve their ability to feign vestibular weakness. This investigation supports the use of scoring computed dynamic posturography results by the formulae of Cevette et al. in separating aphysiologic behavior from vestibular impairment.
Morgan
Stacie S
SS
Department of Otolaryngology-Head and Neck Surgery, University of Texas Health Science Center, San Antonio, Texas 78229-3900, USA.
Beck
William G
WG
Dobie
Robert A
RA
D000328:Adult; D003071:Cognition; D006801:Humans; D008306:Malingering / Q000175:diagnosis*; D008875:Middle Aged; D011187:Posture; D011446:Prospective Studies; D015837:Vestibular Diseases / Q000175:diagnosis*