Adult Inventory of Procrastination Scale (aip): a Comparison of Models with an Italian Sample

The present study analyzed the psychometric proprieties of the Adult Inventory of Procrastination (AIP) by McCown and Johnson (1989) with an adult Italian sample (n = 305) by comparing three construct models. Models included: 1) the original uni-dimensional structure; 2) a Spanish model with two components — lack of punctuality and lack of planning (Díaz Morales, Ferrari, Diaz, & Argumendo, 2006); 3) a Turkish model with two components reflecting positive aspects of avoidance and negative aspects of avoidance (Ferrari, Özer, & Demir, 2009). Moreover, two models using the Adult Inventory of Procrastination and the Decisional Procrastination Scale were analyzed using scores on the AIP: the four-component model of Díaz Morales et al. (2006) and Steel’s (2010) three-factor model of procrastination. Results showed that the original uni-dimensional model provided the best fit. Both internal consistency for reliability, and convergent and discriminant validity with other measures supported the uni-dimensional psychometric properties of the Italian AIP.