Psychometric properties of the Dickman Impulsivity Instrument in suicide victims and living controls of rural China

Background: We are not aware of any of impulsivity trait for Chinese rural youths. This study evaluated the psychometric properties of Dickman Impulsivity Instrument in suicide cases and living controls in rural China. Methods: The participants, 392 suicide victims and 416 controls were respectively selected, and the psychological autopsy method was used to collect information. The Exploratory Factor Analysis was processed to evaluate the construct validity. The Cronbach's alpha was computed to evaluate the internal consistency, and the Spearman rank correlation coefficients between STAI Trait Anxiety Inventory, Coping Responses Inventory and Dickman Impulsivity Instrument were calculated to evaluate the convergent validity. Results: Dysfunctional and Functional impulsivity were extracted for both samples. The mean of DI scores in suicide cases was larger than that in controls, but it was reversed for FI. There were no significant differences between DI and FI in suicide cases, but in controls the mean of DI scores was significantly smaller than that of FI. The Cronbach's alpha was around .863 and .779 respectively for DI and FI scales in suicides, and it was around .746 and .680 in controls. The DI and FI were significantly correlated with each other. Both the DI and FI were correlated with Approach and Avoidance Coping Response Inventory, and both of the scales were grossly independent with Trait Anxiety Inventory in two samples. Conclusion: The results indicated that the Dickman Impulsivity Instrument was adequate to measure impulsivity trait for suicide victims and living controls through proxy data in rural China. (C) 2011 Elsevier B.V. All rights reserved.