The John Jay College of Criminal Justice is a senior college of The City University of New York that emphasizes criminal justice, fire science, and other public service related fields. They have been commissioned to do two studies for the National Review Board, one in 2004 and another in 2006. Their data can be found online on the USCCB website: http://www.usccb.org/issues-and-action/child-and-youth-protection/reports-and-research.cfm