Abstract
The sensitivity of phallometric measures with rapists was investigated using individual rape indices of rapists and non-sex offenders from 14 published and unpublished data sets.Sensitivity (the probability of detecting deviant sexual arousal among rapists) was determined by alternately setting thespecificity (the probability of not detecting deviant sexual arousal among non-sex offenders) at 70%, 80% or 90%. Eight data sets showed sensitivity values equal to, or greater than, 60% when specificity was set at 90%. Stimulus sets that contained more brutal and graphic descriptions of rape produced higher sensitivity values. A conservative rape index cut-off score of 1.0 seems optimal in that it yields moderate sensitivity values while minimizing the number of individuals who are falsely classified as presenting deviant sexual arousal. Conditions that may increase the sensitivity of phallometric assessments are presented and discussed.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Abel, G.G., Barlow, D.H., Blanchard, E.B., & Guild, D. (1977). The components of rapists' sexual arousal.Archives of General Psychiatry, 34, 895–903.
Abel, G.G., Blanchard, E.B., Becker, J.V., & Djenderedjian, A. (1978). Differentiating sexual aggressives with penile measures.Criminal Justice and Behavior, 5, 315–332.
Barbaree, H.E., Marshall, W.L., & Lanthier, R.D. (1979). Deviant sexual arousal in rapists.Behaviour Research and Therapy, 17, 215–222.
Barbaree, H.E., Seto, M.C., Serin, R.C., Amos, N.L., & Preston, D.L. (in press). Sexual arousal to rape in sexual and nonsexual rapist subtypes.Criminal Justice and Behavior.
Baxter, D.J., Barbaree, H.E., & Marshall, W.L. (1986). Sexual responses to consenting and forced sex in a large sample of rapists and nonrapists.Behaviour Research and Therapy, 24, 513–520.
Earls, C.M., & Proulx, J. (1986). The differentiation of francophone rapists and nonrapists using penile circumferential measures.Criminal Justice and Behaviour, 13, 419–429.
Eccles, T. (1990).The clinical utility of the Rape Index. Unpublished doctoral Dissertation, Queen's University, Kingston.
Freund, K., & Blanchard, R. (1989). Phallometric diagnosis of pedophilia.Journal of Consulting and Clinical Psychology, 57, 100–105.
Freund, K., & Watson, R.J. (1991). Assessment of the sensitivity and specificity of a phallometric test: An update of phallometric diagnosis of pedophilia.Psychological Assessment, 3, 254–260.
Harris, G.T., Rice, M.E., Quinsey, V.L., Chaplin, T.C., & Earls, C.M. (1992). Maximizing the discriminant validity of phallometric data.Psychological Assessment, 4, 502–511.
Lalumière, M.L., & Earls, C.M. (1992). Voluntary control of penile responses as a function of stimulus duration and instructions.Behavioral Assessment, 14, 121–132.
Lalumière, M.L., & Quinsey, V.L. (in press). The discriminability of rapists from non-sex offenders using phallometric measures: A meta-analysis.Criminal Justice and Behavior.
Langevin, R., Bain, J., Ben-Aron, M.H., Coulthard, R., Day, D., Roper, V., Russon, A.E., Webster, C.D., & Wortzman, G. (1985). Sexual aggression: Constructing a predictive equation: A controlled pilot study. In R. Langevin (Ed.),Erotic preference, gender identity, and aggression in men: New research studies (pp. 39–76). Hillsdale, NJ: Erlbaum.
Loeber, R., & Dishion, T. (1983). Early predictor of male delinquency: A review.Psychological Bulletin, 94, 68–99.
Looman, J. (1989).Rapists/pedophiles: A distinct group? Unpublished honour's thesis, University of Saskatchewan, Saskatoon.
Malcolm, B. (1992).Rapists assessment data from the Sex Offender Treatment Program of the Regional Treatment Centre, Kingston. Unpublished manuscript.
McGraw, K.O., & Wong, S.P. (1992). A common language effect size statistic.Psychological Bulletin, 111, 361–365.
Prentky, R.A., & Knight, R.A. (1991). Identifying critical dimensions for discriminating among rapists.Journal of Consulting and Clinical Psychology, 59, 643–661.
Proulx, J. (1992, June).Les résponses péniennes de violeurs à deux types de stimuli de viol. Paper presented at the annual convention of the Canadian Psychological Association, Québec City.
Quinsey, V.L. & Chaplin, T.C. (1982). Penile responses to nonsexual violence among rapists.Criminal Justice and Behavior, 9, 372–384.
Quinsey, V.L., & Chaplin, T.C. (1984). Stimulus control of rapists' and non-sex offenders' sexual arousal.Behavioral Assessment, 6, 169–176.
Quinsey, V.L., & Chaplin, T.C. (1988). Preventing faking in phallometric assessments of sexual preference. In R.A. Prentky & V.L. Quinsey (Eds.)Human sexual aggression: Current perspectives (pp. 49–58). New York: Annals of the New York Academy of Sciences.
Quinsey, V.L., Chaplin, T.C., & Upfold, D. (1984). Sexual arousal to nonsexual violence and sadomasochistic themes among rapists and non-sex-offenders.Journal of Consulting and Clinical Psychology, 52, 651–657.
Quinsey, V.L., Chaplin, T.C., & Varney, G. (1981). A comparison of rapists' and non-sex offenders' sexual preferences for mutually consenting sex, rape, and physical abuse of women.Behavioral Assessment, 3, 127–135.
Rice, M.E., Chaplin, T.C., Harris, G.T., & Coutts, J. (1990).Empathy for the victim and sexual arousal among rapists and nonrapists (Report No. 8). Penetanguishene: Mental Health Centre Research.
Rice, M.E., Chaplin, T.C., Harris, G.T., & Coutts, J. (1993).Empathy for the victim and sexual arousal among rapists and nonrapists. Manuscript submitted for publication.
Wydra, A., Marshall, W.L., Earls, C.M., & Barbaree, H.E. (1983). Identification of cues and control of sexual arousal by rapists.Behaviour Research and therapy, 21, 469–476.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Lalumière, M.L., Quinsey, V.L. The sensitivity of phallometric measures with rapists. Annals of Sex Research 6, 123–138 (1993). https://doi.org/10.1007/BF00849303
Issue Date:
DOI: https://doi.org/10.1007/BF00849303