Paul Green

Detecting malingering in head injury litigation with the Word Memory Test

The Word Memory Test (WMT) is a relatively new computer-based test that is designed to measure both verbal memory and biased responding (i.e. malingering). The purpose of this study was to examine the performance of a large sample of patients involved in head injury litigation on the WMT measures of biased responding. The patients were divided into two groups, those with relatively mild head injuries (n = 234) and those with moderate or severe brain injuries (n = 64). The patients with less severe injuries performed significantly poorer on the WMT measures of biased responding.

California Verbal Learning Test indicators of suboptimal performance in a sample of head-injury litigants.

Cutoff scores suggested by Millis, Putnam, Adams, and Ricker (1995) for detecting suboptimal performance on indices from the California Verbal Learning Test (CVLT) were evaluated using data from 193 compensation-seeking participants. All participants claimed to have suffered a blow to the head in an accident causing subsequent deterioration in cognitive function. The participants were divided into those with negligible or possible mild brain injuries and those with clear evidence of moderate to severe brain injuries. In addition to the CVLT, all participants were administered the Computerized Assessment of Response Bias (CARB), a two-alternative forced choice test of recognition memory that is used to detect feigned cognitive impairment. For all CVLT indices, the distributions of outcome (valid vs. suboptimal performance) was unrelated to age and brain injury severity, and only weakly associated with education. However, a significantly higher proportion of males than females obtained scores in the suboptimal performance range. The CVLT indices were not fully redundant with each other with respect to binary participant classifications; substantial disagreement between pairwise classifications was found among those participants who obtained at least one score in the suboptimal performance range. CVLT index classifications were also found to be non-redundant with classifications based on CARB scores. The CVLT may thus add useful data over and above that obtained from symptom validity testing. However, the data suggest that the use of the strategy where any one or more below-cutoff CVLT scores are considered a positive indicator of suboptimal performance may be associated with a higher than acceptable false-positive error rate.

Measuring improvement or decline on the WAIS-R in inpatient psychiatry.

Psychologists in inpatient psychiatric settings sometimes are asked to assess whether patients improve or decline in intellectual functioning. The impetus for this referral question may be a perceived change in psychiatric status, an acute neuropathological event, e.g., a head injury, or a suspicion of an early dementing process. For this study, data from 100 inpatients who completed the WAIS–R on two separate admissions were used to calculate confidence bands for measurement error surrounding test-retest difference scores. The analysis indicated that, if the retest interval is three months or less, significant practice effects must be factored into the interpretation of difference scores. A table for the interpretation of difference scores at different testing intervals is provided.

LEADERSHIP STYLE EMPHASIS AND RELATED PERSONALITY ATTRIBUTES

This study examined differences in personality attributes between supervisors who placed equal emphasis on the people and task dimensions of leadership and those who tended to be exclusively people- or task-oriented. Using the Leadership Opinion Questionnaire as a measure of preference for a particular leadership style and the Sixteen Personality Factor Questionnaire to assess personality attributes, it was found that subjects evidencing a preference for a “balanced” style tended to be more tough-minded, practical, conservative, and group-dependent.

Evaluating Effort with the Word Memory Test and Category Test-Or Not

ABSTRACT As more techniques sensitive to the effects of poor effort are validated, clinicians are faced with the choice of which techniques to use and what to do in the case of discrepancies. We compared the groups identified by the Booklet Category Test (BCT) criteria published by Tenhula and Sweet (1996) and the effort-sensitive measures of the Word Memory Test (WMT; Green, Allen & Astner, 1996) in a large sample seeking compensation after suffering head injuries of varying levels of severity. Results revealed substantial differences between the groups identified by each technique as putting forth suboptimal effort. The groups identified by the WMT scored in a manner similar to samples identified by other investigators exhibiting poor effort. In contrast, the classifications based upon the Category Test decision rules appear to be confounded by true neurocognitive impairment, particularly in individuals who have suffered more severe brain injuries. Caution is warranted in using the Category Test decisio...

Assessing intellectual functioning in persons with schizophrenia spectrum disorders using a seven subtest short form of the WAIS-R

The purpose of this study was to examine the concurrent validity of a Wechsler Adult Intelligence Scale-Revised (WAIS-R) seven subtest short form. Researchers have shown that the IQ scores estimated by this short form correlate highly with full-form IQ scores in several patient populations. We compared the full WAIS-R scores with the seven subtest short form estimated IQs in a sample of patients with psychotic disorders (n = 190). The VIQs, PIQs, and FSIQs estimated by the short form were highly correlated with the full form IQs (rs ranging from 0.95 to 0.98). Similar to previous research, the mean difference scores were small (ranging from one point to virtually no difference). In general, the seven subtest short from has adequate concurrent validity and is suitable for assessing intellectual functioning in persons with psychotic disorders.

Predictive validity of WAIS-R VIQ-PIQ splits in persons with major depression

We selected a sample of patients with depression (N = 70) and used Bayesian analyses to examine the diagnostic predictive validity of the Wechsler Adult Intelligence Scale-Revised Verbal IQ (VIQ) minus Performance IQ (PIQ) difference score for depression. The patients showed average VIQ-PIQ differences in the expected direction (i.e., VIQ > PIQ). However, based on sensitivity, specificity, and positive predictive value statistics, we concluded that the VIQ-PIQ split has very low predictive validity in persons with depression.

Models for Measuring Induced Affective Change: Some Neglected Methodological Considerations

The measurement of affect and other personality characteristics has usually been carried out in a predispositional, correlational framework. However, the measurement of varying levels of affect induced by different treatments during an experiment has received less attention because of the methodological problems involved. Typical weaknesses of research concern test-retest effects, test sensitization, test-wiseness, lack of control groups, inductive construct validity of measures, emotional boundedness, purging effects, and short treatment duration. A manageable design paradigm for gaining sound results on experimentally induced affect is presented.