Relationship between Key Variables in Penile Plethysmograph and Viewing Time Measures of Sexual Arousal in Sex Offending Adult Males

by Cloyd, Lisa Loewinger

Penile plethysmography is amongst the best measures for prediction of sexual recidivism and has been extensively researched. However, there are a variety of criticisms regarding use of penile plethysmography (PPG), including financial investment, significant training needs, lack of standardization, intrusive nature of the measure, extensive time for testing, and inability to use PPG with all groups of sexual offenders (e.g., women and adolescents). Viewing time has been studied, though not as extensively as PPG, regarding detection of sexual interest. This study examined the relationship between Monarch 21 PPG and Affinity viewing time variables, including responses to individual stimuli, a sex deviance differential, and a sex deviance ratio. It was predicted that there would be a significant positive correlation between key variables of the Monarch 21 PPG and Affinity. Overall, the associations found between the Monarch 21 PPG and the Affinity were significant, although the magnitudes of the associations were modest. When considering sexual deviance ratios and differentials (as is typically utilized in PPG literature), there was a small, but significant association between the Monarch 21 PPG and the Affinity. Consequently, it is recommended that more research be done comparing these two sets of measures, further evaluating the Affinity and its predictive validity, and examining the complex arousal pattern shapes, rather than focusing only on a series of discrete variables.