Correlations with both Self-Deception and Impression Management scale scores of the Balanced Inventory of
Desirable Responding ( Paulhus, 1998 ) exceed .70, while correlations with the Marlowe /C0Crowne scale score are
approximately .50.
Divergent/Discriminant
Correlations of the PIM scale with the Structured Interview of Reported Symptoms (SIRS; Rogers et al., 1992)
scale scores are almost uniformly lower, with a correlation of /C0.67 reported for the Defensive Symptom
scale of the SIRS. A variety of cutoff scores for the PIM scale have been suggested to distinguish simulated and
realistic mental health. A raw score of 23, equating to 68T, is more than two standard deviation units above the
mean of the clinical sample, while a mean of 18, equivalent to 57T, is used as a less conservative cutoff, one
which identifies just over 30% of the community sample. Almost 18% of a sample of individuals undergoing
capacity evaluation for child custody scored above the higher cutoff point, while relatively high proportions,
over 80%, of non-clinical samples score above the lower cutoff point of 57T. Three cutoff scores for the NIM
scale are commonly used, equal to or above 73T (one standard deviation over the mean for the normal sample),
equal to or over 84T (one SDover the mean for the clinical sample) and equal to or over 92T, a value that is
two standard deviations above the clinical mean. The manual reports studies finding different identification rates
for a variety of samples. Classification rates as high as 89% are reported in the manual, those being for the identi-
fication of a malingered severe mental disorder. Rates for the identification of feigned specific psychological
disorders are generally lower.
Construct/Factor Analytic
The literature reviewed to date has not located any studies reporting factor analysis of the PAI validity scales.
Location
Morey, L.C. (1991). Personality Assessment Inventory professional manual . Odessa, FL: Psychological Assessment
Resources.
Morey, L.C. (2007). Personality Assessment Inventory (PAI) professional manual . (2nd ed.) Lutz, FL: Psychological
Assessment Resources.
Results and Comments
The fact that identification of distorting individuals is focused on in validity attempts has to be applauded.
Effect sizes for group differences between feigned and honest report are generally statistically significant and
range up to 3.7 standard deviations. Most, however, are in the neighborhood of one standard deviation. Mixed
results have been reported for the utility of the various discriminant analyses developed for use with the PAI.
In one report with psychiatric inpatients, Baity, Siefert, Chambers, and Blais (2007) suggest that one discriminant
function and the NIM scale score were the most sensitive measures for detecting faking bad, while the PIM scale
score was most sensitive for detecting faking good. A formal examination of the utility of the difference score
between NIM and PIM scale raw scores showed that its effect size was not notably different from those provided
by the NIM and PIM scales alone in detecting response styles ( Hopwood, Talbert, Morey, & Rogers, 2008 ).
Gaines, Giles, and Morgan (2013) recently reported that a combination of scores on 7 of the 11 PAI clinical scales
performed better in differentiating feigning from non-feigning inmates of a psychiatric correctional facility than
the NIM scale or PAI discriminant functions for faking. These findings warrant replication and extension to other
populations.
In balance, PAI validity scales for impression manage ment appear to be effective measures despite their
relatively short length and corresponding modest relia bility. Although there is not much evidence in the liter-
a t u r ea sy e t ,i ta p p e a r st h a ti na tl e a s ts o m ec o n t e x t s ,t h e PAI validity indicators offer a degree of incremental
validity over the validity scale scores of the MMPI-2 ( Blanchard, McGrath, Pogge, & Khadivi, 2003 ).Braxton,
Calhoun, Williams, and Boggs (2007) report higher concordance rates between the PIM scale of the PAI and
MMPI-2 Kscale than for the NIM scale. The MMPI-2 validit y scales flagged more cases as suspect than those
on the PAI, with the two scales agreeing in about two thirds of both inpatient and outpatient cases
(Morey, 2007 ).34 2. RESPONSE BIAS, MALINGERING, AND IMPRESSION MANAGEMENT
I. INTRODUCTION: CORE ISSUES IN ASSESSMENT