Incest

Prevalence rates for incest vary widely due to differences of definition, methods of study, and the population source of the data (Glasser et al. 2001). Commonly, studies report prevalence rates of child abuse in general and do not break the abuse into familial and nonfamilial. In the United States in the 1990s, it was estimated that 100,000 to one million cases of incest occur annually, but only about 10 percent of them are reported ( Johnson 1983). Although some research estimates that less than 2 percent of the general population experiences sexual abuse (Kutchinsky 1992), other studies estimate that incest is experienced by 10 to 20 percent of children in the general population (Briere and Runtz 1989; Finkelhor et al. 1990; Russell 1983). A few other countries have published research in English on the prevalence of incest. In Brazil, for example, prevalence estimates range widely from 0.05 percent to 21 percent (Flores, Mattos, and Salzano 1998).

It is not unusual to find very different prevalence rates of incest for males and females, as in the study conducted by Renvoize (1993) who reported that as many as one-third of all girls and one-fifth of boys have experienced incest. Researchers agree that girls are much more often the victims of incest. Others report that the incidence for males is less than half of that for females because a higher proportion of males are sexually abused by adults outside the home by strangers (Carlstedt, Forsman, and Soderstrom 2001; Finkelhor et al. 1990; Gonsiorek, Bera, and LeTourneau 1994). Male incest victims may also report less frequently because they are socialized not to express feelings of helplessness and vulnerability (Nasjleti 1980).

Estimates of the prevalence of incest have risen steadily since the late 1960s as knowledge of child sexual abuse and incest has increased. There is some controversy, however, over the validity of the reported prevalence of incest. The often painful and shameful aspects of sexual abuse within the family make the collection of data very difficult. It is generally thought by professionals that the underreporting of incest is common due to the secrecy, shame, the tendency to blame the victim, and criminal ramifications surrounding incest. However, false reports by children of nonoffending parents, especially in divorce-custody situations, may account for an increase in reported incidents. There has been criticism that therapists may encourage reports through a process of recovering memories forgotten by the patient. Even considering false reporting and misuse of recovering memories, it is still very likely that the number of incest cases is underreported.

Recidivism among incest offenders is estimated at around 8.5 percent, though up to the late 1990s, very few studies had been conducted on this issue, and recidivism is as underreported as are first reports of incest (Quinsey et al. 1995). A study of the sexual recidivism of 251 convicted adult male incest perpetrators in a clinical setting in Ottawa, Canada, found that 6.4 percent had committed another sexual offense six-and-a-half years after their incest conviction (Firestoneet et al. 1999).