More than 10,600 US children said they were molested by priests since 1950 in an epidemic of child sexual abuse involving at least 4 per cent of Roman Catholic priests.
The revelations were published today in two US studies commissioned by Catholic bishops in 2002.
They show the abuse peaked with the ordination class of 1970 from which one in 10 US priests was eventually accused of abuse.
Mr Robert Bennett of the US Conference of Catholic Bishops National Review Board said the abuse of children was a national health problem and described the scandals involving the Catholic church as a crisis of trust and faith.
He said: "It's always bad when a child gets abused but when the abuser wears a collar, it's worse."
The report showed 10,667 children were allegedly victimized by 4,392 priests from 1950 to 2002, but it said the figures depend on self-reporting by American bishops and were probably an undercount.
The Archdiocese of Boston yesterday released local figures from the reports, saying 7 per cent of its priests were accused of abuse in the last 50 years.
A group of academics at the John Jay College of Criminal Justice in New York conducted one of the reports. It said 97 per cent of the dioceses filled out its surveys.
The other report, on the causes and context of the crisis, was written by a team of prominent Catholic lawyers, judges, business people and bishop-appointed professionals on a national review board.
It used interviews with 85 bishops and cardinals, Vatican officials, experts and a handful of victims.
The 145-page report looked at the culture in Catholic seminaries, where priests are trained, and chanceries, or church office, that it said tolerated moral laxity and a gay subculture.
While the report made recommendations for reform, it did not say if church doctrine or rules needed to be changed.