The scientific understanding of pedophilia is largely incomplete, despite significant advances during the last 30 years, according to Barbara Schwartz, who holds a doctorate in psychology.

Schwartz, a Plymouth, Mass., native; is the author of several books on sex offenders and behaviors.

In a Feb. 22 interview with The Catholic Free Press, newspaper of the Worcester diocese, she said pedophilia is a mental disorder that causes a person to develop "a measurable sexual preference for prepubescent children."

This distinction separates pedophiles from the more general category of child molesters, that is, those who sexually abuse children for a Variety of motives other than actual sexual arousal, she said.

Craig Latham, who also holds a doctorate in psychology, thinks that calling pedophilia a disease implies that those who sexually abuse children are not accountable for their actions.

Pedophilia is not inherited through genes nor is it biologically based, he said. Rather it is a learned behavior with an addictive quality that escalates in intensity and frequency. Latham, who is in private practice in Natick, Mass., works primarily with abused adolescents and young adults, some of whom are pedophiles.

Current studies suggest that pedophilia develops at a young age and often is connected to an individual's own victimization at the hands of another, Schwartz said.

Such victimization may lead to the individual acting out his or her abuse on another, something she called repetition trauma. It also may be socially modeled behavior, that is, behavior that an individual witnesses and imitates, she added.

Though many pedophiles were once victims themselves, "it's not a one-to-one ratio," said Evan Graber of Holden, Mass., who has a doctorate in clinical psychology.

Not every child who is sexually assaulted becomes a pedophile and, likewise, not every pedophile was sexually assaulted, said Graber, who is director of outpatient service at You Inc. and works only with juvenile pedophiles.

Exactly what causes pedophilia in those who have not been abused is unknown, he added.

Pedophiles at any age do not look any different from "normal" people, Graber said, which makes it difficult to detect their illness until inappropriate behavior is observed or an allegation is made.

They do, however, share some common traits, according to Latham.

Most pedophiles are male, he noted. Allegations of women making sexual advances toward males are typically underreported because society tends to see such instances as a rite of passage for young men. …