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The Dig Task: A Simple Scent Discrimination Reveals Deficits Following Frontal Brain Damage
Published on: January 4, 2013
Classification accuracy of the portland digit recognition test in traumatic brain injury
K J Bianchini1, C W Mathias, K W Greve
1Department of Psychology, University of New Orleans-Lakefront, LA 70148, USA.
Abstract:
This study examined the classification accuracy of the Portland Digit Recognition Test (PDRT) in traumatic brain injury (TBI). It differs from past studies in assigning patients to malingering and control groups on the basis of compensation-seeking status and the presence of external markers for malingering. Sensitivity and Specificity were.77 and 1.00, respectively. Past research comparing compensation-seekers to noncompensation-seekers reported Sensitivities of.33 or lower (Specificity is always high). This study demonstrates that past research has seriously underestimated the Sensitivity of the PDRT and raises questions about the true Sensitivity of other malingering techniques as well.

