Cross-validation of indicators of malingering: a comparison of nine neuropsychological tests, four tests of malingering, and behavioral observations

Archives of Clinical Neuropsychology 17 (2002) 1 – 23 Cross-validation of indicators of malingering A comparison of nine neuropsychological tests, four tests of malingering, and behavioral observations$ Tina Hanlon Inmana, David T.R. Berryb,* a AIDS Neurological Center, University of North Carolina-Chapel Hill, Chapel Hill, NC, USA Department of Psychology, University of Kentucky, 115 Kastle Hall, Lexington, KY 40506-0044, USA b Accepted 10 July 2000 Abstract Few studies to date have cross-validated indicators of malingering that have been suggested on various neuropsychological tests. This study presents data cross-validating several indicators of malingering on neuropsychological tests, as well as on tests of malingering and via behavioral observations. It incorporates methodological recommendations by Rogers [Researching dissimulation. In: R. Rogers (Ed.), Clinical assessment of malingering and deception (pp. 309– 327). New York: Guilford Press.] resulting in an ecologically valid design utilizing college students with a history of mild head injury as analog malingerers. Results indicated that the Letter Memory Test (LMT) and the Digit Memory Test (DMT) attained the highest hit rates for the detection of malingering, while the sensitivity of many other measures declined on cross-validation. D 2001 National Academy of Neuropsychology. Published by Elsevier Science Ltd. Keywords: Malingering; Cross-validation; Letter memory test The evaluation of malingering in neuropsychological assessment has become increasingly important in recent years with the growth of forensic evaluations. In many cases, neuropsychological test data provide the only potentially objective evidence of deficits. This is especially true in cases of mild head injury where neuroimaging tests are often negative and neurological signs are often absent. The ability of neuropsychologists to judge the motivation $ The study reported in this article was derived from the dissertation of Tina Hanlon Inman. * Corresponding author. Tel.: +1-859-257-5451; fax: +1-859-323-1979. E-mail addresses: (T.H. Inman), (D.T.R. Berry). 0887-6177/01/$ – see front matter D 2001 National Academy of Neuropsychology. 0887-6177(00)00073-1 Downloaded PII: from Shttps://academic.oup.com/acn/article-abstract/17/1/1/2053 by guest on 21 June 2018 2 T.H. Inman, D.T.R. Berry / Archives of Clinical Neuropsychology 17 (2002) 1–23 of patients during testing has been criticized in the past (Faust, Hart, & Guilmette, 1988; Faust, Hart, Guilmette, & Arkes, 1988; Heaton, Smith, Lehman, & Vogt, 1978), however, several promising indicators of malingering have been developed in recent years. Previously published indicators of malingering include behavioral rating scales, scores on standard neuropsychological tests, and tests designed specifically for the detection of malingering. Research on the use of behavioral rating scales has been limited. Several researchers have suggested the use of behavioral rating scales for the determination of cooperation in neuropsychological assessment (Allen, Lewis, Wyman, & Coyne, 1989; Frederick, Sarfaty, Johnston, & Powel, 1994; Snow, Tierney, Zorzitto, Fisher, & Reid, 1990). The study by Frederick et al. (1994) is the only study to date that has used a behavioral rating scale in an experimental design including possible malingerers. Their results suggested that behavioral rating scales may be useful in detecting malingering, however, further research is needed with more clearly defined groups of possible or simulated malingerers. Numerous studies have been done examining various indicators of malingering on standard neuropsychological tests. Studies have included all or parts of the following tests: the Benton Visual Retention Test (Benton & Spreen, 1961), the Bender–Gestalt Test (Bruhn & Reed, 1975; Schretlen & Arkowitz, 1990), the Rey–Osterrieth Complex Figure Test (Bernard, 1990; Bernard, Houston, & Natoli, 1993), the Wechsler Memory Scales — Revised (Bernard, 1990; Bernard et al., 1993; Greiffenstein, Baker, & Gola, 1994; Iverson & Franzen, 1996; Mittenberg, Azrin, Millsaps, & Heilbronner, 1993; Trueblood & Schmidt, 1993), the Memory Assessment Scales (Beetar & Williams, 1995), the Rey Auditory Verbal Learning (AVLT) Test (Bernard, 1990, 1991; Bernard et al., 1993; Binder, Villaneuva, Howieson, & Moore, 1993; Greiffenstein et al., 1994; Greiffenstein, Gola, & Baker, 1995; Hiscock, Branham, & Hiscock, 1994), the California Verbal Learning Test (Frederick et al., 1994; Rose, 1993; Trueblood, 1994; Trueblood & Schmidt, 1993), the Recognition Memory Test (Iverson & Franzen 1994; Millis, 1992, 1994), the Halstead– Reitan Neuropsychological Battery (Goebel, 1983; Heaton et al., 1978; Hiscock et al., 1994; Mittenberg, Rotholc, Russell, & Heilbronner, 1996; Trueblood & Schmidt, 1993), the Luria–Nebraska Neuropsychological Battery (Mensch & Woods, 1986), the Wechsler Adult Intelligence Scales — Revised (WAIS-R) (Bernard et al., 1993; Greiffenstein et al., 1994, 1995; Heaton et al., 1978; Iverson & Franzen, 1994, 1996; Martin, Hayes, & Gouvier, 1996; Mittenberg et al., 1993; Trueblood & Schmidt, 1993), the Symbol Digit Modalities Test (Hiscock et al., 1994), and the Wisconsin Card Sorting Test (WCST) (Bernard, McGrath, & Houston, 1996). Many of the above studies have shown promising results for the use of indicators of malingering on neuropsychological tests. Some of the most well-supported measures are the Digit Span subtest from the WAIS-R (Greiffenstein et al., 1994, 1995; Iverson & Franzen, 1994, 1996; Martin et al., 1996; Trueblood, 1994; Trueblood & Schmidt, 1993), the Rey AVLT (Greiffenstein et al., 1994, 1995; Hiscock et al., 1994), the Recognition Memory Test (Iverson & Franzen, 1994; Millis, 1992, 1994), and the Halstead–Reitan Neuropsychological Battery (Mittenberg et al., 1996; Trueblood & Schmidt, 1993). Although there have been many studies examining these indicators, the indicators are rarely cross-validated, they lack consistent cutting scores, and they are rarely directly compared with other methods of assessing motivation. Advantages of these indicators are they add no additional testing to the T.H. Inman, D.T.R. Berry / Archives of Clinical Neuropsychology 17 (2002) 1–23 3 battery and they provide potentially useful information regarding brain dysfunction. A disadvantage is they are prone to false-positive diagnoses of malingering due to inadequate validation of cutting scores and discriminant functions. The third method of evaluating motivation during neuropsychological testing involves using tests specifically designed for the detection of malingering. Several tests have been designed for this purpose, including the Rey’s 15-Item Test (FIT) (Rey, 1964, cited in Lezak, 1995), Rey’s 15-Item Word List (Rey, 1941, cited in Lezak, 1995), Rey’s Dot Counting Test (Rey, 1941, cited in Lezak, 1995), Symptom Validity Testing (Pankrantz, 1979), the Portland Digit Recognition Test (Bin (...truncated)