Classification of child molesters by plethysmographic assessment of sexualarousal and a self-report measure of sexual preference

The present study examined the extent to which the use of multiple measures of pedophilic interest improved on the diagnostic accuracy of any single m easure. Seventy-two child molesters completed a self-report card-sort measu re of sexual interest, as well as direct monitoring of penile response (pen ile plethysmograph-PPG) when presented with erotic slides or audio material . The reliability of ail measures was high (alpha .91-.96). All three measu res of pedophilic interest (i.e., card sort, PPG slides, PPG audio) signifi cantly differentiated boy-object (n = 20) and girl-object child molesters ( n = 52). The card-sort measure showed the greatest classification accuracy and was the only measure to significantly improve accuracy, once the other two modalities were considered. Consideration of all three modalities provi ded classification accuracy (91.7%) greater than any single measure.