According to a new study focusing on consumer information, nearly 25 percent of group health plans provided through Affordable Care Act (“ACA”) exchanges may be violating federal mental-health parity laws.

The study was led by associate professor Colleen Barry of the Johns Hopkins Bloomberg School of Public Health, and is published in the current issue of Psychiatric Services. To conduct the study, Barry and her colleagues reviewed benefit brochures offered in two state-run exchanges during the first ACA enrollment period between 2013 and 2014.

The study alleges two significant problems. First, according to the study plans in the exchange often had financial disparities. For example, the study found that plans would include different co-pays for mental-health and substance-use disorder services from medical/surgical services. Second, according to the study some mental-health and substance-use disorder services had more stringent “prior authorization” requirements than their medical/surgical counterparts. These disparities, the report suggests, can dissuade people from selecting more expensive plans with more generous mental-health and substance-use-disorder benefits. According to the study, because mental-health and substance-use disorder services are often more expensive than medical/surgical services, insurers may benefit when consumers are dissuaded from joining plans with more generous mental-health and substance-use disorder benefits.

But some observers have taken issue with the study’s methodology. As a recent USA Today article notes, representatives of both America’s Health Insurance Plans (AHIP) and Cigna Insurance have argued that the study improperly focuses on what consumers see before buying the plans. Clare Krusing of AHIP explained that the study ignored the claims history for the plans studied, which data is more indicative of compliance with federal mental-health parity laws. Cigna CEO David Cordani added that cost sharing levels for behavioral health are the same as for other specialists.

In light of the final federal mental-health parity regulations, it is clear that federal mental health parity does not always require that mental-health and substance-use-disorder benefits have the exactly same levels of either quantitative or non-quantitative treatment limitations as do medical/surgical benefits. Hence, it is difficult to ascertain whether this study identified actual parity violations, or simply instances of disparity (which may or may not be permitted under the final parity regulations, depending on the circumstances). In any event, however, the study is a helpful reminder that mental-health and substance-use-disorder benefits will require frequent “check ups” in order to best steer clear of potential mental-health parity concerns.