Sexual abuse can have negative consequences for children during the time of abuse as well as later in life, according to several recent research reviews. Initial effects reportedly have included fear, anxiety, depression, anger, aggression, and sexually inappropriate behavior in at least some portion of the victim population. Long-lasting consequences reportedly have included depression, self-destructive behavior, anxiety, feelings of isolation and stigma, poor self-esteem, difficulty in trusting others, a tendency toward revictimization, substance abuse, and sexual maladjustment. In addition, researchers have noted that there is widespread belief that there is a "cycle of sexual abuse," such that sexual victimization as a child may contribute to perpetration of sexual abuse as an adult. Such a pattern is consistent with social learning theories--which posit that children learn those behaviors that are modeled for them--and also with psychodynamic theories--which suggest that abusing others may help victimized individuals to overcome childhood trauma. Critics have argued that empirical support for the cycle of sexual abuse is weak, and that parents are unduly frightened into thinking that little can be done to mitigate the long-term effects of sexual abuse. There remain many unanswered questions about the risk posed by early sexual victimization, as well as about the conditions and experiences that might increase this risk (such as number of victimization experiences, age of the victim at the time of the abuse, and whether the abuse was perpetrated by a family member). There are also questions about factors that may prevent victimized children from becoming adult perpetrators (such as support from siblings and parents or positive relationships with other authority figures). Answers to such questions would be useful in developing both prevention strategies and therapeutic interventions. Studying the relationship between early sexual victimization and later perpetration of sexual abuse is methodologically difficult. If researchers take a retrospective approach, and ask adult sex offenders whether they experienced childhood sexual abuse, there are problems of selecting a representative sample of offenders, finding an appropriate comparison group of adults who have not committed sex offenses but are similar to the study group in other respects, minimizing errors that arise when recalling traumatic events from the distant past, and dealing with the possibility that offenders will purposely overreport childhood abuse to gain sympathy or underreport abuse to avoid imputations of guilt. A prospective approach--selecting a sample of children who have been sexually abused and following them into adulthood to see whether they become sexual abusers--overcomes some of the problems of the retrospective approach, but it is a costly and time-consuming solution. In addition, researchers choosing the prospective approach still face the challenge of disentangling the effects of sexual abuse from the effects of other possible problems and stress-related factors in the backgrounds of these children (e.g., poverty, unemployment, parental alcohol abuse, or other inadequate social and family functioning). This requires the selection of appropriate comparison groups of children who have not been sexually abused and children who have faced other forms of maltreatment, as well as the careful measurement of a variety of other explanatory factors. We collected, reviewed, and analyzed information from available published and unpublished research on the cycle of sexual abuse. Identifying the relevant literature involved a multistep process. Initially, we identified experts in the sex offense research field by contacting the Department of Justice's Office of Juvenile Justice and Delinquency Prevention and Office of Victim Assistance, the National Institute of Mental Health's Violence and Traumatic Stress Branch, the American Psychological Association, and academicians selected because of their expertise in the area. These contacts helped identify experts in the field, who in turn helped identify other experts. We also conducted computerized searches of several on-line databases, including ERIC (the Education Resources Information Center), NCJRS (the National Criminal Justice Reference Service), PsycINFO, Dissertation Abstracts, and the National Clearinghouse on Child Abuse. We identified 40 articles on the cycle of sexual abuse issued between 1965 and 1996. Four of these reviewed the literature in the area; of these, two were published in 1988, one was published in 1990, and one was published in 1991. Of the remaining articles, 23 presented findings from retrospective research studies, which began with a sample of known adult sex offenders of children and sought to determine (by asking the offenders) whether they were sexually abused during childhood. Another four presented findings from two prospective research studies, which began with samples of sexually victimized children and tracked them into adulthood to determine how many became sex offenders. Of the original 40 articles, we excluded 5 because they presented findings only, or primarily, on adolescent sex offenders against children, and an additional 4 because we were unable to obtain them. For the studies in our review, we recorded the quantitative results, summarized the methodologies used, and summarized the authors' conclusions about the cycle of sexual abuse. Each study was reviewed by two social scientists with specialized doctoral training in evaluation research methodology. Conclusions in this report are based on our assessment of the evidence presented in these studies. We sent the list of research articles to two experts, both of whom have done extensive research in the field, to confirm the comprehensiveness of our list of articles. In addition, as a final check, we conducted a second search of computerized on-line databases in March 1996 to ensure that no new research articles or reviews had been published since our original search in October 1995. We sent a draft copy of our report for comment to the two experts previously consulted, as well as to one additional expert, to ensure that we had presented the information about the research studies accurately.Their technical comments were incorporated where appropriate. We did not send a draft to any agency or organization because we did not obtain information from such organizations for use in this study. We did our work between October 1995 and August 1996 in accordance with generally accepted government auditing standards. There was no consensus among the studies we reviewed that being sexually abused as a child led directly to the victim's becoming an adult sexual abuser of children. However, some studies did conclude that it might increase the risk that victims would commit sexual abuse later. A majority of the retrospective studies noted that most sex offenders had not been sexually abused as children, and the two prospective studies showed that the majority of victims of sexual abuse during childhood did not become sex offenders as adults. The 4 review articles we obtained, which collectively covered roughly two-thirds of the 25 studies we reviewed, concluded that the evidence from these studies was insufficient to establish that being sexually abused as a child is either a necessary or a sufficient condition for the victim's becoming a sexual abuser as an adult. We reviewed 23 retrospective studies. Appendix I provides additional information on these studies. All but one of the retrospective studies focused on adult male sex offenders, and in most studies the offenders sampled were imprisoned or in some type of treatment program. However, these studies varied considerably in the types of child sexual abusers studied, whether control or comparison groups were used, and if so, the types of individuals in these groups. The retrospective studies also varied considerably in their findings and conclusions. The percent of adult sex offenders against children identified as being sexually abused as children themselves ranged from zero to 79 percent. This variation partially reflects differences across studies in how childhood sexual abuse was defined, as well as other differences in study methodology. This variation may also reflect the differences in the types of child sex offenders studied. For example, both Hanson and Slater (1988) and Garland and Dougher (1988) concluded from their reviews of retrospective studies that offenders who selected male children as victims were more likely to have been sexually abused themselves than were offenders against female children. A few of the studies found that sex offenders of children were more likely to have been sexually abused as children than were members of control groups composed of noninstitutionalized nonoffenders. However, many studies found that, when compared with other types of sex offenders (e.g., rapists or exhibitionists) and other types of nonsexual offenders (i.e., men incarcerated for nonsexual crimes), adult sex offenders of children were not necessarily more likely to have been sexually abused as children. According to several researchers, the relationship between childhood sexual victimization and adult perpetration of sexual offenses against children is complex and requires measurement and analysis of a host of factors. For example, it has been postulated that adult sexual offending is not simply a result of the experience of childhood sexual victimization, but also of other factors such as age at onset of the abuse, nature of the abuse, stability of the caregiver, and/or physical abuse. Studies that collect data on such additional factors may add to our understanding of what types of sexual abuse, perpetrated under what conditions against what types of child victims, are associated with what types of adult sexual offending against what types of victims under what types of conditions. However, while such retrospective studies can help explore factors possibly related to adult sexual offending, they cannot establish the importance of these factors in predicting adult sexual offending. The reason for this is discussed in the following section. The retrospective studies we reviewed had several shortcomings that precluded our drawing any firm conclusions about whether there is a cycle of sexual abuse. First, the studies focused on known sex offenders of children (i.e., offenders who have been detected, arrested, or convicted, or who had been referred or had presented themselves for treatment), and these offenders may not be typical or representative of all sex offenders against children. Second, self-reports of childhood sexual abuse obtained from known sex offenders are of questionable validity. Known offenders may be motivated to overreport histories of abuse to gain sympathy or to excuse their own offenses. Third, where comparison or control groups were used, attempts to match group members to sex offenders of children on factors possibly related to being sexually abused or abusive were typically limited; few of the studies attempted to control for such factors statistically. Finally, one of the major shortcomings of these retrospective studies is that they cannot reveal how likely it is that a person who has been sexually abused as a child will become a sexual abuser in adulthood. For example, even if 100 percent of sexual abusers of children were sexually abused as children, this would not necessarily mean that sexual abuse causes abused children to become abusers themselves. It may be that only a small percentage of sexually abused children become sex offenders against children. Determining how likely victims of childhood sexual abuse are to become adult sex offenders requires that a sample of sexually abused children be followed forward in time, rather than the histories of sex offenders be traced backward. Our review of the literature identified two research studies (described in four articles) that have used a prospective approach in examining the cycle of sexual abuse. One of these studies is part of a larger study of the cycle of violence. Widom is the primary researcher in the larger study, which is still ongoing. It involves a cohort of 908 substantiated cases of child abuse (physical and/or sexual) or neglect processed through the courts between 1967 and 1971. These abuse/neglect cases were restricted to children who were 11 years of age or younger at the time of the abuse or neglect incident. They included 153 sexually abused children, 160 physically abused children, and 697 neglected children. This prospective study also includes a control group of 667 individuals who had no record of abuse or neglect and who were either born in the same hospitals or attended the same elementary schools as the abused children. The control and study group members were matched on sex, age, race, and approximate family socioeconomic status. Local, state, and federal official arrest records containing information recorded up to June 1994 were used to determine how many of the study and control group members were arrested for sex offenses. Table 1 shows results pertaining to sex offenses from the most recent analyses based on this larger study. The study did not distinguish whether the sex offense was perpetrated against a child or an adult. Compared to the control group, a higher percentage of those who had been sexually abused, physically abused, or neglected as children were arrested as adults for any sex crime, for prostitution, and (among males) for rape or sodomy. To determine how different the study groups were from the control group, Widom statistically controlled for such differences between the groups as age, race, and sex; calculated odds ratios; and performed statistical tests. The results indicated that the differences between the sexually abused group and the control group in the odds of arrest for any sex crime or for rape or sodomy separately were not statistically significant. Sexually abused children were significantly more likely to have been arrested for prostitution, however. Twenty-three to 27 years later, sexually abused children were nearly four times more likely to have been arrested for prostitution. On the other hand, members of the childhood neglect study group were significantly more likely than members of the control group to have been arrested for any sex crime or for prostitution. Because it could allow researchers to discern the likelihood of victims becoming abusers, the prospective approach is methodologically superior to the retrospective approach. Widom's study, however, has several limitations. First, published work from the study has so far relied solely on official arrest data, which may fail to identify some offenders (those who avoid detection or arrest). Second, the study groups of victimized children were identified by using records of substantiated cases of abuse or neglect that were processed through the state courts. Such cases may represent only the most severe instances of abuse and may not be generalizable to all children who have been abused or neglected. Finally, the number of sexually abused males in the abused/neglected sample was small (a total of 24). Statistical comparisons based on small numbers of cases should be interpreted with caution, since small sample sizes may not yield reliable estimates. We located one other study that used a prospective design and followed sexually victimized children into early adulthood. This study sampled 147 boys under the age of 14 who were seen in the emergency room of an urban hospital because of sexual abuse between 1971 and 1975. The researchers also collected data on a comparison sample of boys of the same race and roughly the same age who were seen in the same emergency room at roughly the same time for reasons other than sexual abuse. In the period 1992 to 1994, official juvenile and adult arrest records for the entire victim and comparison sample were collected, and the researchers attempted to locate and interview as many of the men as possible. Fifty of the 147 boys in the victim sample, and 56 of the 147 boys in the comparison sample, were interviewed. They were asked to self-report instances of sex-offending, and were also asked a number of other questions about their family of origin, sexual history, history of sexual victimization, psychological functioning, drug and alcohol use, and criminal behavior. As shown in table 2, the study found little difference between the victim and comparison samples in the percentages that were arrested for, or that self-reported, sex offenses. According to the researchers, one explanation for this finding is that the victim and comparison samples are not as different as originally intended with respect to their having been victims of child sexual abuse. For instance, in the comparison group, 40 percent of the 56 men interviewed reported that they had themselves been sexually abused. Furthermore, 55 percent of the men in the victim sample did not recall, or at least did not report to interviewers, that they had been sexually abused. When the researchers reanalyzed the data and compared all victims (from both the victim sample and the comparison sample) with the remaining nonvictimized members of the comparison group, they did not find a significant difference between the two groups in the likelihood of becoming a sex offender. These findings must also be interpreted with caution, however, because no-difference findings are sometimes attributable to comparing small samples rather than to a real absence of difference between groups. The generalizability of these findings may be limited since the sample of sexually abused boys (and the matched comparison group) is neither a random sample nor a sample that is representative of the general population of children at risk of such abuse. Over 80 percent of the boys sampled were African-American, and a disproportionate number of the men who were interviewed were from poor families and had criminal records. About one-third of the interviewed men who were sexually abused as boys, and about one-fifth of all of the men interviewed, were incarcerated at the time of interview. The Williams et al. study is instructive in that it points to a number of difficulties involved in conducting prospective studies of the relationship between childhood victimization and adult offending. These difficulties include (1) the need to determine whether members of comparison groups were victims of sexual abuse, and (2) the need to employ more than a single outcome measure of offending. Of 15 men who self-reported any sex offense, only 5 had an arrest record for a sex offense; and of 14 men who had been arrested for a sex offense, only 5 self-reported a sex-offending behavior. A number of studies have been done on the cycle of sexual abuse, many of which were reviewed in this report. Most of the studies were retrospective in design; that is, they began with a sample of known sex offenders of children and sought to determine whether they were sexually abused during childhood. The chief limitation of the retrospective studies is that studying a known group of sexual offenders cannot provide any direct information about the extent to which children who are sexually abused become sexual offender as adults. The two studies we reviewed that were prospective in design attempted to overcome this limitation by identifying samples of sexually victimized children and tracking them into adulthood to determine how many became sex offenders. These studies also had limitations, which made it difficult to reach any definitive conclusions about the cycle of sexual abuse. However, in spite of their limitations, overall, the retrospective studies, prospective studies, and research reviews did indicate that the experience of childhood sexual victimization is quite likely neither a necessary nor a sufficient cause of adult sexual offending. Further research would be necessary to determine what kinds of experiences magnify the likelihood that sexually victimized children will become adult sexual offenders against children and, alternatively, what kinds of experiences help prevent victimized children from becoming adult sexual offenders against children. We are sending copies of this report to the Ranking Minority Member of the House Subcommittee on Crime and the Chairman and Ranking Minority Member of the Senate Committee on the Judiciary. Copies will also be made available to others upon request. The major contributors to this report are listed in appendix II. Please call me at (202) 512-8777 if you have any questions about this report.

Summary:
Pursuant to a congressional request, GAO reviewed research studies regarding the cycle of sexual abuse, focusing on the likelihood that individuals who are victims of sexual abuse as children will become sexual abusers of children in adulthood. GAO found that: (1) there was no consensus among the 23 retrospective and 2 prospective studies reviewed that childhood sexual abuse led directly to the victim becoming an adult sexual abuser; (2) the retrospective studies, which sought to determine whether a sample of known sex offenders had been sexually abused as children, differed considerably in the types of offenders studied, use of control or comparison groups, and definition and reporting of childhood sexual abuse; (3) although some of the retrospective studies concluded that childhood sexual abuse may increase the risk that victims will commit sexual abuse later, most of the studies noted that the majority of sex offenders had not been sexually abused as children; (4) the prospective studies, which tracked sexually abused children into adulthood to determine how many became sex offenders, studied sample populations that may not be representative of the entire population of childhood sexual abuse victims; and (5) the prospective studies found that victims of childhood sexual abuse were not more likely than nonvictims to be arrested for sex offenses.