Person reliability of psychiatric patients' responses to a psychopathology inventory.

Person-reliability indices can assist clinicians in determining the interpretability of a patient's responses to the Basic Personality Inventory (BPI). Using an initial sample of 65 psychiatric patients, we found that: (1) different person-reliability indices showed modest evidence of psychometric adequacy and tended not to be confounded with general psychopathology; (2) a content consistency index of person reliability was predictably related to other item change variables, whereas within-session profile stability was related to across-session measures of profile stability: and (3) evidence for the ability of person-reliability indices to moderate the validity of clinical criteria was weak. Results provide cautious support for a multidimensional conceptualization of the person reliability construct on the BPI but demand further evaluation of the clinical utility of person reliability indices.

Clinical reliabilities and validities of the microcomputerized Basic Personality Inventory.

With a population of 64 adult psychiatric patients, we examined the psychometric properties of a microcomputerized version of the Basic Personality Inventory (BPI). Reliability information suggested that the basic and factor scales were internally consistent and stable. Clinical staff ratings were used as criteria, and analyses indicated that BPI scales possessed convergent validity. Overall, our findings add to the growing literature on the clinical utility of the Basic Personality Inventory.

A Regression Equation for the Parallel Analysis Criterion in Principal Components Analysis: Mean and 95th Percentile Eigenvalues.

Monte Carlo research increasingly seems to favor the use of parallel analysis as a method for determining the "correct" number of factors in factor analysis or components in principal components analysis. We present a regression equation for predicting parallel analysis values used to decide the number of principal components to retain. This equation is appropriate for predicting criterion mean eigenvalues and was derived from random data sets containing between 5 and 50 variables and between 50 and 500 subjects. This relatively simple equation is more accurate for predicting mean eigenvalues from random data matrices with unities in the diagonals than a previously published equation. Moreover, given that the parallel analysis decision rule may be too dependent on chance, our equation is also used to predict the 95th percentile point in distributions of eigenvalues generated from random data matrices. Multiple correlations for all analyses were at least .95. Regression weights for predicting the first 33 mean and 95th percentile eigenvalues are given in easy-to-use tables.

Test-retest reliability of the Hopelessness Scale and its items in a university population.

In a study that used 149 university undergraduates and a 3-week test-retest interval, the stability of the Hopelessness Scale was examined. Scale scores and item responses demonstrated high test-retest reliabilities. Additional analyses indicated significant sex differences on the Hopelessness Scale. It was concluded that the Hopelessness Scale's stability fulfills a prerequisite for it to be a predictor of long-term suicidal risk.

Assessing the person reliability of an individual MMPI protocol.

This study investigated various measures commonly employed to assess the person reliability of an individual Minnesota Multiphasic Personality Inventory (MMPB protocol. Specifically, relationships among indices of person reliability and the standard MMPI validity scales were examined using the responses of 82 subjects who completed the MMPI on two occasions separated by 1 week. Person reliability indices were based on within-occasion responses to identical and to psychologically similar items, and on three across-occasion response consistency measures. The validity scales, namely, the L, F, K, and Cannot Say scales, showed higher test-retest stability than the within-occasion person reliability indices. Further, the validity scales and person reliability indices appeared to reflect multiple facets of dependable responding. Interestingly, an individual's tendency to change responses to MMPI items from the test to the retest was significantly predictable. Clinical implications of these findings were derived.

Effects of psychotropic drugs and psychiatric illness on vocational aptitude and interest assessment.

This study examined the vocational aptitude and interest scores of 326 inpatients at a large urban psychiatric hospital. The inpatient group performed significantly below the adult normative mean on eight of nine General Aptitude Test Battery (GATB) aptitude measures; the single exception was Verbal Aptitude. Further, GATB aptitude scores (adjusted for age and education) were significantly lower for patients who were receiving (N = 210) psychotropic medication than for patients who were not receiving (N = 114) psychotropic medication, again with the exception of Verbal Aptitude. Differentiation of patients into subsamples who were receiving particular drugs or drug combinations indicated that phenothiazines in combination with Anti-Parkinsonians were associated with the poorest GATB performances. Interestingly, self-reported vocational interests were not related in any systematic fashion to receiving medication. A variety of explanations that may account for these findings, including drug side-effects and severity or type of psychiatric disorder, were investigated. Implications for vocational counselors were discussed.