Detection of feigned tactile sensory loss using a forced-choice test of tactile discrimination and other measures of tactile sensation.

Abstract

Intentional exaggeration of disability is a risk in work injuries but is hard to reliably detect clinically. This study examined the accuracy of tactile sensory threshold and forced-choice discrimination measures in detecting feigned sensory loss. Participants (n = 80) were randomly assigned to one of four sensory loss groups: (1) none; (2) partial; (3) full; or (4) feigned. Sensory data were collected for the upper extremities. Tactile thresholds greater than 0.5 g, discriminability less than 0.50, or forced-choice scores less than 90% were associated with a very low probability of false-positive errors. Below-chance scores are definitive evidence that the sensory loss is intentionally feigned. Scores beyond cut-offs should raise the clinician's suspicion of malingering if there is no physical basis for sensory loss.