Catanzaro also said that the board urged church leaders "a number of times" to suspend accused priests during investigations, but that the archdiocese had ignored that recommendation.
"Our priority has always been to keep kids safe," she said.
Catanzaro declined to identify the seven priests or to discuss details of the allegations against them.
Still, the admission was likely to stir new questions about the suspended priests' activities, why the review board never heard all their cases, and what the archdiocese's commitment is to rooting out abuse and protecting children.
"The procedures they have set up are nothing more than window dressing in an attempt to pacify and stall and stonewall the victims from getting a true day in court," said Kenneth Millman, a Berks County lawyer whose firm has represented dozens of alleged victims of archdiocesan priests.
On Tuesday, Cardinal Justin Rigali announced that the 21 priests would be placed on administrative leave - prohibited from distributing sacraments or living in parish residences - pending a reexamination of old accusations against them.
The archdiocese declined to publicly name the priests or to describe the complaints, except to say they involved sexual abuse or inappropriate behavior around minors.
The Inquirer and other news outlets have published their names and parishes.
Donna Farrell, a spokeswoman for the archdiocese, declined Thursday to discuss cases before the review board or the board's process, but said the suspensions "represent a broad range of complaints - from allegations of sexual abuse to boundary issues or inappropriate behavior."
Farrell also said the archdiocese was "actively engaged" with the review board and considering its request to expand the kinds of cases it reviews.
The suspensions followed a grand-jury report last month that accused the archdiocese of failing to reform and of keeping 37 priests in active ministry despite allegations against them.
The grand jury took particular aim at the review board, which it said had ignored "very convincing evidence" of abuse or misconduct, or at least sufficient evidence to suspend a priest pending an investigation.
Days after that report, the archdiocese suspended three priests who the grand jury said had been credibly accused but left in their posts.
Gina Maisto Smith, a former sex-crimes prosecutor hired by the archdiocese to reexamine the other cases, recommended the 21 new suspensions this week.
Smith cleared an additional eight after reviewing the allegations against them. Of the rest, one is no longer a priest, two are sick and no longer in active ministry, and two work in religious orders outside the Philadelphia area. Archdiocesan officials have notified the superiors in their orders.
The review board dates to 2003, one of a raft of reforms U.S. bishops ordered in response to the sex-abuse scandal roiling the church.
The Philadelphia board, which includes Catholics, non-Catholics, and many with experience in child welfare, meets quarterly. Its cases are handpicked by the archdiocese and are typically abuse claims serious enough to warrant a look, but too old or flawed for prosecutors to investigate.
Board members don't take testimony, but instead review transcripts of interviews and other information supplied by the alleged victim, archdiocesan officials, and the accused priest, if he chooses, or his representative. The board votes on whether there's sufficient evidence to recommend action against the priest.
Since 2003, the board reviewed 61 cases. In 37 cases, or nearly two-thirds, it found the allegations credible enough to recommend a priest's removal, Catanzaro said. One recommendation is pending, she said.
Among the rest, seven involved the priests placed on leave this week. Three more were claims against priests who have since retired. The others are dead or no longer in ministry, Catanzaro said.
The review board's purview is narrow, she said. It considers only cases involving sexual abuse, not general misconduct or boundary issues, such as a priest striking a child, making a lewd comment, or drinking in front of children.
It also has no authority to examine allegations against priests in religious orders - which staff many of the archdiocesan schools - because those priests aren't under the cardinal's authority. And it doesn't review allegations pending in the courts.
Catanzaro said she was told that Smith, the ex-prosecutor reviewing the old cases, was given more information and used broader standards to evaluate the priests than the review board had been told to use. That's a good thing, she said.
"The more eyes that look at the available evidence," she said, "the better."
Contact staff writer John P. Martin at 215-854-4774 or email@example.com.
Contributing to this article were Inquirer staff writers Craig R. McCoy, Jeremy Roebuck, and Kathleen Brady Shea.