Examining the Psychometric Properties of the Sexual Initiation Strategies Scale (SISS): A New Self-Report Measure of Sexual Aggression Perpetration History.

Psychometrically-sound measures of sexual aggression are essential for identifying risk factors for perpetration and examining the behavioral impact of prevention interventions. This project reports on the psychometric evaluation of a new measure of sexual perpetration-the Sexual Initiation Strategies Scale (SISS)-which was designed to correct for weaknesses in prior measures. In Study 1, scores on the SISS demonstrated reasonable convergent and divergent validity and test-rest reliability among a sample of mixed gender college students ( N  = 575). Participants were more likely to endorse having engaged in sexually aggressive behavior on the SISS than on two other measures of sexual aggression. In Study 2, rates of endorsement on the SISS also were higher than on the most commonly-used measure of perpetration in a community sample of men and women ( N  = 551) in which gay, lesbian, and bisexual participants were oversampled. In general, the SISS seemed to perform well as a measure of sexual aggression perpetration in both men and women and in those reporting both same- and other-gender sexual aggression. Advantages and disadvantages of the SISS as compared to other measures are discussed.