Sexual Offenders' Modus Operandi: A Comparison of Structured Interview and Questionnaire Approaches

Clinical practice has long supported the use of structured interviews with both perpetrators and victims of sexual offenses. However, empirical studies have not examined the differential utility of structured interviews and self-report questionnaires for obtaining information about sex offenders' modus operandi. This investigation compared the ability of these two assessment approaches to provide details regarding sexual offenders' modus operandi from the perspective of victims, incarcerated offenders, and offenders in outpatient treatment. Study findings indicated that structured interviews and questionnaires yielded consistent information for most items across participant groups. For modus operandi items that were not consistently reported, more information was obtained via the questionnaire format. However, in one instance, the interview format obtained significantly more information about incarcerated offenders' use of threats and coercion to gain victim co operation in sexual activity. Implications for child sexual abuse prevention, offender and victim treatment, and future research are discussed.