The 6 nonoverlapping primary scales of the Structured Interview of Reported Symptoms (SIRS) were subjected to taxometric analysis in a group of 1,211 criminal and civil examinees in order to investigate the latent structure of feigned psychopathology. Both taxometric procedures used in this study, mean above minus below a cut (MAMBAC) and maximum covariance (MAXCOV), produced dimensional results. A subgroup of participants (n = 711) with valid Minnesota Multiphasic Personality Inventory-2 (MMPI-2) protocols were included in a second round of analyses in which the 6 nonoverlapping primary scales of the SIRS and the Infrequency (F), Infrequency-Psychopathology (Fp), and Dissimulation (Ds) scales of the MMPI-2 served as indicators. Again, the results were more consistent with dimensional latent structure than with taxonic latent structure. On the basis of these findings, it is concluded that feigned psychopathology forms a dimension (levels of fabrication or exaggeration) rather than a taxon (malingering-honest dichotomy) and that malingering is a quantitative distinction rather than a qualitative one. The theoretical and clinical practice implications of these findings are discussed.

Relationships among Structured Interview of Reported Symptoms (SIRS) scores and Minnesota Multiphasic Personality Inventory--2 (MMPI-2) F(p) and F scores were examined for 63 suspected malingerers evaluated at either of two psychiatric facilities. Despite differences between facilities in terms of seriousness of subjects' offenses, mean scores on the malingering tests were similar. Cutting scores for F(p) and F resulting in substantial correspondence between these scales and the SIRS were derived. Use of the cut score for F(p) proposed by Arbisi and Ben-Porath (1995) resulted in less agreement with the SIRS than did a lower cut score. No substantial difference between F(p) and F in each scale's overall agreement with the SIRS was observed. A principal components analysis of the SIRS primary scales produced two factors, interpreted as Overreporting of Symptoms and Implausible Symptoms. F(p) was observed to correlate significantly with Implausible Symptoms but not with Overreporting of Symptoms; F was significantly correlated with both factors.

TO THE EDITOR: In their report in the May issue, Louzon and her coauthors (1) employed statistics associated with survival analysis to assess whether item 9 of the nine-item Patient Health Questionnaire (PHQ-9) has clinical utility for predicting suicide mortality. Item 9 asks, "Over the past two weeks, how often have you been bothered by thoughts that you would be better off dead or of hurting yourself in some way?" Response options are "not at all," "several days," "more than half the days," and "nearly every day."At several points in the article, Louzon and colleagues seem to imply that their analysis showed that item 9 of the PHQ-9 can be clinically useful for predicting suicide. I propose that an alternative, more pertinent consideration of their data supports a markedly different inference.If we are evaluating a test that will be used to "predict suicide," as per the title of the article, our concern must be with the probability that a person with a positive score on the test will die by suicide (known as the positive predictive value, or PPV) and the probability that a person with a negative score on the test will not die by suicide (negative predictive value, or NPV). Data presented by the authors in Table 2 allow for the computation of these values for their sample.Taking a "positive" score to mean that a person responded "nearly every day" to item 9, one would predict 8,589 suicides; however, only 22 of those participants died by suicide (PPV5.26%). Taking a response of "not at all" as a "negative" score, one would predict that 343,635 would not die by suicide; of those participants, 343,413 did not die by suicide. Although this results in a respectable NPV of 99.94%, it nevertheless means that 222 of the 244 participants in this comparison who did die by suicide were falsely predicted to not be at risk of suicide. (Similar results are obtained when a "not at all" response is compared with any or all other responses to item 9.) Practically speaking, a clinician who predicted that a person in Louzon and colleagues' sample would die by suicide, on the basis of the person's reporting any suicidal ideation on item 9, would have been wrong over 99.5% of the time; hence, the item has no clinical utility for predicting suicide.Louzon and her colleagues studied a sample of veterans. Although the prevalence of suicide among veterans may be higher than in the general population, it is still very low in real terms. A very low base rate for a characteristic that we wish to predict makes it well-nigh impossible to obtain a useful level of PPV.

The MacArthur Study of Mental Disorder and Violence produced an instrument for classifying hospitalized psychiatric patients according to their risk of behaving violently following discharge. The instrument, Classification of Violence Risk (COVR) has been computerized and is now commercially available to clinicians. A validation study performed by the original researchers showed that when the instrument was applied to a new sample of patients, it demonstrated a considerable reduction in positive predictive power. Potential factors affecting the instrument's accuracy in applied settings are reviewed. It is concluded that, until additional research clarifies uncertainty about the instrument, clinicians would do well to be very cautious in utilizing COVR results to make judgments as to violence risk, particularly when the test results suggest a high risk of future violence.

Short forms of the Wechsler Adult Intelligence Scale-Revised (WAIS-R) developed by A. Kaufman, T. Ishikuma, and J. Kaufman-Packer (1991) were cross-validated on 207 male and 133 female psychiatric inpatients and outpatients (aged 16-79 years) with low mean IQ. Results showed that the short forms displayed psychometric properties comparable to those observed in the WAIS-R standardization sample. Validities were stable across differences in S age, gender, race, inpatient versus outpatient status, years of education, and diagnosis. In contrast to D. Boone's (1992a) findings, the 4-subtest short form evidenced greater predictive accuracy than either the 2-or the 3-subtest form. Users are cautioned that it is inappropriate to classify individuals according to level of intelligence on the basis of short-form IQ scores.Contributing to an ongoing quest for brief, valid methods of assessing global intelligence, Kaufman and his colleagues (Kaufman, 1990;Kaufman, Ishikuma, & Kaufman-Packer, 1991) have formulated three "amazingly" short forms of the Wechsler Adult Intelligence Scale-Revised (WAIS-R): a dyad (Information and Picture Completion), a triad (Information, Picture Completion, and Digit Span), and a tetrad (Arithmetic, Similarities, Picture Completion, and Digit Symbol). A feature that distinguishes these short forms from those proposed by others is their remarkable brevity in terms of the time required for administration and scoring. By way of illustration, Kaufman et al. noted that their tetrad takes less time to administer than Silverstein's Vocabulary and Block Design dyad, but it possesses comparable reliability (.93 vs. .94) and slightly higher validity (.95 vs. .91;