Robin Watson

Assessment of the sensitivity and specificity of a phallometric test : an update of phallometric diagnosis of pedophilia

The specificity and sensitivity of the phallometric test of an erotic preference for minors was assessed. The specificity was determined to be 96.9% if using a group of sex offenders against female adults and 80.6% if using a group of paid volunteers. Test results of 27 sex offenders against at least 2 female children each and of 22 offenders against at least 2 male minors each (either against children or against pubescents, but not against both), demonstratedsensitivitiesof 78.2% for heterosexual pedophiles and 88.6% for homosexual pedophiles or hebephiles. From these test sensitivities, the percentage of subjects preferring minors in a group of offenders against only 1 female child each, a group of offenders against at least 1 female child and at least 1 female pubescent each, and a group of offenders against only 1 male minor each (child or pubescent) were determined as being 44.5%, 74.6%, and 86.7%, respectively. The differential diagnosis between the various erotic preferences can be established by means of the phallometric test, which uses continuous recording of penile volume changes while a subject views potentially arousing pictures on screens or listens to such taped narratives (Abel, Becker, Murphy, & Flanagan, 1981). The current study was limited to the phallometric test of pedophilia and homosexual hebephilia as it is used in the differential diagnosis between pedophilia or homosexual hebephilia and gynephilia (Freund, Diamant, & Pinkava, 1958; Quinsey, Steinman, Bergersen, & Holmes, 1975).

Does sexual abuse in childhood cause pedophilia: An exploratory study

The reliability of the notion that pedophilia is caused by sexual abuse in childhood was explored by examining retrospective self-reports of 344 males. Included in the study were 77 heterosexual pedophiles, 54 homosexual pedophiles, 51 nonpedophilic sex offenders against children, 36 sex offenders against physically mature females, 75 heterosexual paid volunteers who erotically preferred mature females, and 51 homosexual clients who preferred mature males. For each sex offender the differential diagnosis of an erotic preference for minors vs. a preference for physically mature partners was made by means of the phallometric test of erotic gender and age preferences. The analysis of self-reports confirmed that the proportion of pedophiles who report having been sexually abused in childhood by mature persons is larger than that of men who were not charged for or accused of a sex offense against a child though the difference is relatively small (28.6 vs. 13.9 and 10.7% for the heterosexual pedophiles and the two groups of gynephiles, respectively, and 25.9 vs. 11.8% for the homosexual pedophiles and androphiles, respectively). Further analysis demonstrated, however, that pedophiles who admitted having an erotic interest in children significantly more often claimed that they had been sexually abused as children than pedophiles who did not admit having such feelings. This interdependence renders the reliability of these self-reports questionable.

Signs of feigning in the phallometric test

Abstract The first part of the study tested the validity of the conjecture that three particular patterns, occurring in phallometric results, are signs of feigning. In all three cases the outcome supported this conjecture. Part Two showed that feigning a spurious preference for sex (gender) of partner is more difficult than feigning a spurious preference in respect to partner age, and that the degree of difficulty of the latter depends on whether or not the S was already familiar with the phallometric test, and on the version of the phallometric test for age preference and sex preference used.

Mapping the boundaries of courtship disorder

The courtship disorder hypothesis maintains that voyeurism, exhibitionism, toucheurism‐frotteurism, and the preferential rape pattern are expressions of the same disorder (courtship disorder). Earlier studies had shown that with the exception of the preferential rape pattern these paraphilias co‐occur to a reasonably high degree. The present study (1) demonstrated that the preferential rape pattern co‐occurs with the above reasonably well established expressions of courtship disorder to a higher degree than other main paraphilic activity patterns do and (2) supported the conjecture that in addition to an erotic preference for unfamiliarity of target person‐or‐object (noted by earlier authors), three other paraphilic target‐person or object preferences may be connected with courtship disorder, though they are not at all virtually obligatory as is erotic unfamiliarity. These are choosing children and adults alike as target persons of the paraphilic activities, non‐gender dysphoric transvestism, and fetishism.

The value of self-reports in the study of voyeurism and exhibitionism

Self-reports about patterns of sexual behavior among voyeurs and exhibitionists were examined. Some of their reported experiences were compared with those of other sex offenders and community controls. Four hundred and thirty-seven patients, 92 university student controls and 35 controls with a lower educational level were examined. The self-reports of voyeurs were used to construct a scale for the assessment of voyeurism in cooperative individuals. The self-reports of exhibitionists provided information about the development of their pattern of erotic behavior. It was found that: (a) about one third to one half of the exhibitionists masturbated while exposing and during fantasies about exposing; (b) nearly two thirds of them admitted they had also masturbated in a public place though they knew nobody could see; (c) more than half experience the act of exposing as an invitation to intercourse and about one third as a substitute for intercourse with the target person; (d) the desired reaction from the target person was quite diverse although approximately one third wanted to sexually arouse her, and (e) their inclination to see prostitutes is more likely motivated by the impersonal kind of sexual interaction with prostitutes than by a particular preference for fellatio. The study also confirmed that obscene telephone calling, which occurs also with other anomalous erotic preferences, was connected particularly to exhibitionism.

The proportions of heterosexual and homosexual pedophiles among sex offenders against children: An exploratory study

Previous investigations have indicated that the ratio of sex offenders against female children vs. offenders against male children is approximately 2:1, while the ratio of gynephiles to androphiles among the general population is approximately 20:1. The present study investigated whether the etiology of preferred partner sex among pedophiles is related to the etiology of preferred partner sex among males preferring adult partners. Using phallometric test sensitivities to calculate the proportion of true pedophiles among various groups of sex offenders against children, and taking into consideration previously reported mean numbers of victims per offender group, the ratio of heterosexual to homosexual pedophiles was calculated to be approximately 11:1. This suggests that the resulting proportion of true pedophiles among persons with a homosexual erotic development is greater than that in persons who develop heterosexually. This, of course, would not indicate that androphilic males have a greater propensity to offend against children.

Erotic Gender Differentiation in Pedophilia

Five groups of males were compared on penile volume changes elicited from viewing short movie strips and slides of nude children and adults of both genders. Subject groups were sex offenders against adult females, volunteer controls who erotically preferred adult females, volunteer controls who erotically preferred adult males, heterosexual pedophiles, and homosexual pedophiles. Pedophiles differentiated erotically between females and males less than males who erotically preferred physically mature partners.

A Comparison of Incestuous Biological and Stepfathers

Biological and stepfathers who committed incestuous acts on their daughters were compared on sexual history and preference and on personality, using the Phallometric Test of Erotic Preference (Freund & Blanchard, 1989), the Clarke Sex History Questionnaire (Langevin, et al, 1990), and the Minnesota Multiphasic Personality Inventory (MMPI). The cases were drawn from a data base of 200 incest offenders seen for psychological assessment. Results showed that the two groups of fathers did not differ significantly in their penile responses to pictures of men, women, boys, and girls, and most showed largest responses to adult females. However a significant percentage of both groups showed largest responses to children, indicating pedophilia. Although there was considerable individual variation in sexual history, offenders in both groups had most of their sexual experiences with adult females. Experiences with males were infrequent and limited to adults. The two groups showed few differences in personality. Nevertheless substantial numbers of offenders in both groups showed anxiety, disturbed family background and confused thinking. The results overall showed few differences between incestuous biological and stepfathers in sexual history and preferences and in personality. Similar dynamics appear operative in the two groups, i.e., pedophilia, limited sexual history, and personality pathology are present in selected cases. Possible group differences in other factors prominent in sexual offenders, e.g., substance abuse or neuropsychological impairment, have yet to be examined.

Gender identity disorder and courtship disorder

A hypothetical connection between gender identity disorder and courtship disorder was investigated in 274 heterosexual male patients of the following types: nontransvestic fetishists for female attire; transvestic fetishists; patients with gender identity disorder of adolescence and adulthood, nontranssexual type; and transsexuals. Of these patients, 53 had also demonstrated one or more of the putative expressions of courtship disorder. The proportion each of these types contributed to this group of 53 patients with a courtship disorder was compared with the same types proportional contribution to the group of 221 gender identity patients without a courtship disorder. The transvestic fetishists contributed a significantly larger percentage and the transsexuals a significantly smaller percentage of individuals to the group with a courtship disorder than to that without a courtship disorder. Theoretical implications of this asymmetry are discussed.

A comparison of sex offenders against female and male minors

Male sex offenders against minors were grouped according to age and sex of victims, and according to whether they had offended against one or more than one minor. Cases of incest or courtship disorder were not included in the study. Among offenders against female children, the number of one-case offenders was substantially larger than that of multicase offenders. The opposite was true of offenders against male children, and there was no significant difference between one-case and multicase offenders against female or male early adolescents. If these counts reflect corresponding prevalences within sex offenders against minors in a Western cultural setting, some inferences can be made from these comparisons.