The study focuses on the many differences among the 50 states and Washington, D.C. But it also carves out a section devoted to access to mental health services in the post-Patient Protection and Affordable Care Act/Medicaid expansion era.

"While the number of uninsured is dropping nationwide, the report also shows that insurance doesn't necessarily translate into access to care," the organization's report states.

"There remains a significant workforce issue, with too few psychiatrists, individuals facing large out-of-pocket costs, and many patients having to wait months for an appointment. Because of state differences in Medicaid expansion and marketplace types, whether or not one has access to insurance, whether insurance is affordable, and how complicated access can be depends largely on the state in which you reside.

Along with state differences in exchanges and expansion, states vary considerably in how they choose to implement their public mental health system."

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The report notes that a web of polices, from federal to state to county to municipal levels, are intertwined in a system that eventually determines the degree of access those with health coverage have to mental health services.

"States and counties have considerable choice in how and how much they use the available federal support for their constituents. For example, each state sets its own eligibility criteria for traditional Medicaid and CHIP. States also choose how much of the state budget will be spent on mental health treatment in the public system. Together, this collaboration of federal and state policies and funding streams, comprise the "public" mental health system," the report states. Frequently, those with mental health issues are not being adequately served by this system, the report said.

Using its 15-factor system, Mental Health America produced the following Top 5 states for access and for lack of access.

States with the lowest prevalence of mental illness and highest rates of access to care:

1. Massachusetts
2. Vermont
3. Maine
4. North Dakota
5. Delaware

States with the highest prevalence of mental illness and lowest rates of access to care:

1. Arizona
2. Mississippi
3. Nevada
4. Washington
5. Louisiana

"States that rank in the top 10 [for access] are in the Northeast and Midwest, while states that rank in the bottom 10 are in the South and the West," the study reported.

The study also identified a significant difference in states that ranked high, and low, for access for adults and those that ranked high, and low, for access for youth.

States that ranked high in access for adults:

1. Massachusetts
2. New Jersey
3. Hawaii
4. Maryland
5. Connecticut

For youth:

1. Vermont
2. North Dakota
3. Wisconsin
4. Iowa
5. Maine

States with the highest prevalence of mental illness and lowest rates of access to care for adults [the bottom five]:

1. Mississippi
2. Arizona
3. Oklahoma
4. Arkansas
5. Washington

The bottom five for youth:

1. Nevada
2. New Mexico
3. Montana
4. Louisiana
5. Washington