Plutchik's Impulsivity Scale: A Rasch Testlets Model Analysis in Peruvians

The present study aimed to assess the psychometric properties of Plutchik's Impulsivity Scale (PIS, Plutchik & Van Praag, 1989) using Rasch models. 1160 Peruvian university students aged 16 to 34 participated in the study. It was found that the testlets model exhibited superior fit indices (SRMS=.044, AIC=40439.50, BIC=40540.63) compared to the unidimensional Andrich rating scale proposal (SRMS=.102, AIC=41273.89, BIC=41364.91), given the presence of local dependency, because of the existence of direct and inverse items. A satisfactory reliability of .71 was obtained from measurements calculated using the Expected A Posteriori (EAP) method. The differences between the three items were identified based on sex. In conclusion, the PIS is a test that has met the minimum psychometric standards on Peruvian college samples.