Performance test correlates of impulsivity and its component factors
A lack of consensus about the definition of impulsivity has led to difficulty in its measurement. This is a key issue in research on suicide, where impulsiveness appears to play an important role in suicidal risk. Impulsivity self-report scales exhibit low intercorrelations, are subject to response biases, and multiple subfactors have been identified on most instruments. Performance tests may be both less sensitive to response biases and more precise measures of the underlying dimensions of impulsivity. The current study evaluated relationships between three different performance measures of impulsivity (Time Production, Stop Signal Reaction Time Test, and Complex Reaction Time Test) and standard self-report scales in 40 non-patient subjects. The three performance tests were compared to a composite aggression/impulsivity index derived from three separate self-report scales (Barratt Impulsiveness Scale or BIS, Buss-Durkee Hostility Inventory, and Brown-Goodwin Aggression History), and to a well validated impulsiveness scale containing both general and subfactor scores of impulsive behavior (BIS). It was hypothesized that each performance test assessed a unique aspect of impulsivity, and that a combination of these tests would provide a better estimate of general impulsivity than any one score alone. The performance measures were not significantly correlated with one another. In combination, they did not significantly predict the composite aggression/impulsivity score, but were significantly associated with the total score on the specific impulsiveness measure (BIS). In turn, each performance test was most strongly correlated with the subfactor score on the BIS representing the dimension that it was hypothesized to measure: Time Production with Cognitive Impulsiveness, Stop Signal with Motor Impulsiveness, and Complex RT with Nonplanning Impulsiveness. The power of this study was limited, given the observed effect sizes, and there were few highly impulsive subjects, but the pattern of results was similar to that predicted. These findings support the notion that impulsiveness is a multidimensional construct, and that multiple measures, including both performance tests and well-validated self-reports, provide the most effective means of assessing impulsivity in a comprehensive and clinically useful fashion. ^
"Performance test correlates of impulsivity and its component factors"
(January 1, 2003).
ETD Collection for Fordham University.