[Identifying malingering symptoms of balance disorders by computerized dynamic posturography]

To develop an objective criteria with computerized dynamic posturography (CDP) for identification of non-organic or malingering symptoms of balance disorders.

One hundred and four normal subjects were instructed to feign balance disturbance after naturally performing on CDP. Paired t-test was used to determine if there was significant difference of CDP equilibrium scores between normal and malingering performance. The CDP records including raw curve of 50 subjects were critically evaluated by previously published seven criteria in indicating malingering performance. If the sensitivity of a criterion was greater than 90%, it would be accepted as our laboratory's identifying criterion. The CDP records of remaining 54 subjects were used to test the sensitivity and specificity of the accepted criteria.

There were statistically significant differences of CDP equilibrium scores between normal and malingering performance (P < 0.01). The mean equilibrium scores of malingering performance were lower than that of normal performance. The sensitivity and specificity of our criteria for identifying malingerers were 92.5% and 98.2%, respectively.

It is necessary to identify malingering performance before analyzing the CDP equilibrium scores. Our identifying criteria of malingerers seems to be quite useful and accurate.