A study has found that New York's Riker's Island, Chicago's Cook County Jail and the Los Angeles County Jail are the largest mental health institutions in the nation.

15 percent of the inmates of those three jails are mentally ill, making penal institutions, not hospitals, the three largest U. S. mental health institutions, say Members of the International Association for Forensic and Correctional Psychology.

The association charged a committee to revise their psychological standards for jails, prisons, correctional facilities and agencies, which were first published in 1980.

The revised standards, published in the journal Criminal Justice and Behavior, will benefit institutional security and help integrate former inmates back into the community, and may reduce litigation due to inadequate correctional mental health services, say the committee members.

Committee chair Richard Althouse says in a statement, "Offenders, mentally ill or not, entrusted to the custody of correctional facilities and agencies, benefit in a number of ways from the highest quality of rehabilitative and mental health services."

Althouse and colleagues hope the revised standards, which include organizational policies and ethical principles to govern areas such as intake, staffing, suicide prevention and intervention, keeping records and research will guide administrators and clinicians in providing optimal mental health services. (With Inputs from Agencies)