The psychology of spite and the measurement of spitefulness.

Spite is an understudied construct that has been virtually ignored within the personality, social, and clinical psychology literatures. This study introduces a self-report Spitefulness Scale to assess individual differences in spitefulness. The scale was initially tested on a large sample of 946 college students and cross-validated on a national sample of 297 adults. The scale was internally consistent in both samples. Factor analysis supported a 1-factor solution for the initial pool of 31 items. Item response theory analysis was used to identify the best performing of the original 31 items in the university sample and reduce the scale to 17 items. Tests of measurement invariance indicated that the items functioned similarly across both university and national samples, across both men and women, and across both ethnic majority and minority groups. Men reported higher levels of spitefulness than women, younger people were more spiteful than older people, and ethnic minority members reported higher levels of spitefulness than ethnic majority members. Across both samples, spitefulness was positively associated with aggression, psychopathy, Machiavellianism, narcissism, and guilt-free shame, and negatively correlated with self-esteem, guilt-proneness, agreeableness, and conscientiousness. Ideally, this Spitefulness Scale will be able to predict behavior in both laboratory settings (e.g., ultimatum games, aggression paradigms) and everyday life, contribute to the diagnosis of personality disorders and oppositional defiant disorder, and encourage further study of this neglected, often destructive, trait.