Researchers say they have clear and detailed evidence of the inequitable delivery of mental health care services for disadvantaged Australians. Introduced in 1975, Australia's national health insurance scheme Medicare (originally Medibank) was envisioned to deliver the most equitable and efficient means of providing health insurance coverage for all Australians.

However, the paper published in the Medical Journal of Australia demonstrates inequity and a lack of universality of mental health care delivery, they write. Professor Graham Meadows, School of Clinical Sciences, said the results showed Australia had a multi-tier rather than universal system. "People living in disadvantaged and rural areas typically receive a mental health service model characterized by lower volumes of service and provided by less highly trained providers."

The study found that utilisation of psychiatric and clinical psychologist services was two to three times greater in affluent areas in Melbourne and Sydney (City of Bayside and North Sydney Council) compared with disadvantaged suburbs (City of Greater Dandenong and the City of Blacktown).

"Disturbingly, we know there are greater levels of psychiatric disorder in areas with greater socio-economic disadvantage, so we should expect a fully equitable mental health care system showing a corresponding usage pattern," said Professor Meadows.

In November 2006, the Australian government introduced an initiative called Better Access to Mental Health Care ('Better Access') consisting of new Medicare Benefit Schedule (MBS) items to improve access to psychiatrists, psychologists, and general practitioners.

"Obtained under the Freedom of Information Act, we undertook a detailed analysis of more than 25 million instances of care from 2007 to 2011 of all Medicare-supported mental health service delivery across Australia," said Professor Meadows.

Evaluation of the Better Access program highlights uptake rates for Psychological Therapy Services (PTS) decrease as levels of socio-economic disadvantage increase.

Dr Joanne Enticott, Deputy Director and Coordinator of Health Services Research, Southern Synergy, Monash University said among people with comparable levels of diagnosable mental health problems, it seemed easier for the socio-economically advantaged to pass through the filters to specialist care.

"In other words, the criteria for stepping up a level of care may be different, and the disadvantaged may need higher levels of distress or disturbance to secure specialized levels of care. For the more disadvantaged even if they get care, they may get a shorter course of care than someone from a more affluent area," Dr Enticott said.

While the study does not offer specific solutions to this complex issue, the researchers note the likely influence of co-payments as a disincentive to accessing care. Higher paid specialists such as psychiatrists and clinical psychologists also tend to practice closer to home, resulting in an inequitable distribution of service availability.

Professor Meadows said the findings demonstrated the Better Access initiative - while for many perhaps is providing better access - could be seen as failing on tests of equity.

"We hope our research will contribute to debate and discussion around policy incentives and strategies that work towards universal and equitable delivery of mental health care for all Australians," he said.

Professor Meadows is Director of Southern Synergy, the Monash Health Adult Psychiatry Research Training and Evaluation Centre, School of Clinical Sciences, Monash University.