A new national study concludes that costs might not increase if workers are given the same access to coverage for mental health and substance abuse services as they have for other medical care.

The findings were based on an analysis of thousands of people covered by federal health plans who received behavioral health services through managed care programs. Limits on days of coverage, deductibles and other restrictions were no different for mental health care than for physical health care.

Researchers concluded that offering equal access to behavioral health coverage -- a concept known as parity -- "can improve insurance protection without increasing total costs." The findings were published today in the New England Journal of Medicine.

Other studies have reached similar conclusions, though the latest study is larger and more rigorous, said Dr. Howard Goldman, the principal researcher and a professor of psychiatry at the University of Maryland School of Medicine.

Many states, including Pennsylvania, already require that certain mental health services be covered. But consumer advocates contend that there are often gaps in coverage and that some employers aren't covered by those laws.

Efforts also are under way in Congress to "override those state laws in an effort to make insurance more affordable for small business," said Ralph Ibson, a vice president for the National Mental Health Association.

Consumer groups suggest that national legislation is needed to require employers to offer parity for behavioral health care. The study noted that parity "has been the Holy Grail of mental health policy for decades."

But many employers have opposed requirements that they offer parity "even if the data suggest that this isn't going to be a big burden," said Dr. Russ Newman, executive director for professional practice for the American Psychological Association.

The study published today focused on persons covered by the Federal Employees Health Benefits program. They were offered mental health and substance abuse benefits on a par with medical benefits beginning in January 2001.

Researchers compared claims patterns from seven Federal Employee health plans, analyzing data from a random sample of 20,000 enrollees per plan.

Data were obtained for two years before and two years after parity in behavioral health care began. The study focused on people who were continuously enrolled in a plan. Researchers also analyzed data from a matched comparison group.

The study found that rates of use and spending increased during the study period for all plans. The increase in use might be due in part to a lessening of the stigma concerning mental health treatment, Dr. Goldman said.

A statistically significant increase in use associated with parity, however, was noted in only one plan. A significant decrease occurred in another plan, and no significant difference occurred in the other five plans.

For beneficiaries who used behavioral health services, spending attributable to parity decreased significantly for three plans and did not change significantly for four plans.

The implementation of parity also was associated with significant reductions in out-of-pocket consumer spending in five of seven plans.

"The primary concern has been that the existence of parity would result in large increases in the use of mental health and substance abuse services," researchers concluded. But they said that in the plans studied, "those fears were unfounded."

Amanda Austin, manager of legislative affairs for the National Federation of Independent Business, questioned whether findings from a study of federal beneficiaries were applicable to her members. Forty-two percent offer health benefits and most employ three to nine people, she said, noting her group is opposed to mandated parity for mental health services.

In Pennsylvania, a 1998 law requires some employers to provide coverage for schizophrenia, bipolar disorder and other mental illnesses, noted Gwen Lehman, executive director of the Pennsylvania Psychiatric Society. Plans must provide coverage for at least 30 days of inpatient coverage and 60 outpatient visits a year, she said.

But she noted that co-pays and other cost-sharing can be higher for mental health care than for other medical care. And the law doesn't apply to small employers or to large employers who self-insure -- that is, provide coverage without purchasing it from a health plan.