The scope of sex abuse accusations against Roman Catholic clergy since 1950 appears to be much greater than previously estimated, an Associated Press review of reports from dioceses has found.

The U.S. church will make an unprecedented, nationwide accounting of abuse claims and costs later this month, and some bishops already have started releasing local figures. The AP contacted dioceses across the country and found that 1,341 clergy members have been accused of molesting minors, with more than half the dioceses yet to report.

“What it’s really doing is showing us in black and white that the problem is much worse than any of us thought,” said Sue Archibald, president of The Linkup, a Kentucky-based victim advocacy group.

Statistics have yet to be released by some archdioceses that have faced hundreds of allegations, including Boston and Los Angeles.

A January 2003 review by The New York Times counted 1,205 accused priests nationwide over five decades. Survivors First, an advocacy group compiling its own list from media reports and lawsuits, has counted 1,800.

But Paul Baier of Survivors First said he compared the numbers his organization collected with reports from 41 dioceses and found the dioceses’ local statistics were double what he had counted.

“If those trends continue across 195 dioceses, we can see the number that’s self-reported by the bishops being twice as high as the names in our public database,” Baier said.

The figures the AP compiled are part of a first-of-its-kind national survey the bishops commissioned from the John Jay College of Criminal Justice. By opening themselves up to greater scrutiny, the bishops hope to restore trust in their leadership after waves of scandal over abusive priests. The report is due out Feb. 27.

The national survey won’t break down statistics by individual diocese, but bishops are free to release local figures, and many said they were doing so to fulfill their pledge of transparency in the wake of the crisis that erupted two years ago.

Determining how many priests actually were guilty of abuse is difficult, since many cases were not reviewed by law enforcement and most of the claims involve alleged misconduct that occurred decades ago.

The National Review Board, a lay watchdog panel that the bishops formed, has overseen the study and plans to also release the results of its own investigation into how the crisis occurred.