Over the past 20 years, the plethysmograph has evolved into a sophisticated computerized instrument capable of measuring slight changes in the circumference of the penis. Plethysmograph is a diagnostic method used to assess sexual arousal by measuring the blood flow (tumescence) to the penis during the presentation of sexual stimuli (audio/visual) in a laboratory setting. The plethysmograph provides the identification of clients' arousal in response to sexual stimuli and the evaluation of therapeutic efficacy. If offenders are internalizing methods taught to control their deviant arousal, there is a decrease in deviant arousal and an increase to positive appropriate arousal. There are over 350 published research papers in the scientific literature that document its validity and reliability as an assessment procedure.
Use of the Penile Plethysmograph in the Assessment and Treatment of Sex Offenders Report of the Interagency Council on Sex Offender Treatment to the Senate Interim Committee on Health and Human Services and the Senate Committee on Criminal Justice January, 1993 (Adobe Acrobat format, 38 KB)
Use of the Penile Plethysmograph (PPG) in the Assessment and Treatment of Sex Offenders, Council on Sex Offender Treatment, 2004 (Adobe Acrobat format, 36 KB) New!
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