P1: HDT/HGL/HGA P2: GDR/FJT/GAV QC: GNI
Sexual Abuse: A Journal of Research and Treatment [saj] PP427-369602 April 3, 2002 8:31 Style ﬁle version Nov. 19th, 1999
Sexual Abuse: A Journal of Research and Treatment, Vol. 14, No. 3, July 2002 (
A Comparison of Modiﬁed Versions of the Static-99
and the Sex Offender Risk Appraisal Guide
Kevin L. Nunes,
John M. Bradford,
David M. Greenberg,
and Ian Broom
The predictive validity of 2 risk assessment instruments for sex offenders, modiﬁed
versions of the Static-99 and the Sex OffenderRisk Appraisal Guide, was examined
and compared in a sample of 258 adult male sex offenders. In addition, the inde-
pendent contributions to the prediction of recidivism made by each instrument and
by various phallometric indices were explored. Both instruments demonstrated
moderate levels of predictive accuracy for sexual and violent (including sexual)
recidivism. They were not signiﬁcantly different in terms of their predictive accu-
racy for sexual or violent recidivism, nor did they contribute independently to the
prediction of sexual or violent recidivism. Of the phallometric indices examined,
only the pedophile index added signiﬁcantly to the prediction of sexual recidivism,
but not violent recidivism, above the Static-99 alone.
KEY WORDS: sex offenders; recidivism; prediction; assessment.
The ability to identify sex offenders who are at high risk to reoffend provides
the criminal justice system with the potential to prevent further harm to the com-
munity by these offenders. As well, some management decisions, such as civil
commitment, require risk assessment. Unstructured clinical judgement has been
shown to be a relatively inaccurate method of predicting sexual recidivism (Hall,
1988; Hanson & Bussi`ere, 1998; Quinsey & Maguire, 1986). Actuarial methods
have increasingly received attention in the sexual recidivism prediction litera-
ture and have demonstrated predictive accuracy superior to unstructured clinical
School of Psychology, University of Ottawa, Ontario, Canada.
Sexual Behaviors Clinic and Forensic Service, Royal Ottawa Hospital, Canada.
University of Western Australia, Graylands Hospital Campus, Perth, Australia.
Department of Psychology, Carleton University.
To whom correspondence should be addressed at School of Psychology, University of Ottawa,
120 University Private, Ottawa, Ontario, Canada K1N 6N5; e-mail: firstname.lastname@example.org.
2002 Plenum Publishing Corporation