A FREEZE on increases to Medicare rebates could mean GPs across the country resort to their own co-payments to make up the $8 per consultation shortfall.
The impact is expected to be greater in regional areas because it will make it harder for doctors to have a viable business.
Research on the impact of the Abbott government's freeze on increases to the rebate was published in the Medical Journal of Australia yesterday.
Health Minister Sussan Ley ruled out a government-imposed co-payment on GP visits. But the government has not abandoned the rebate freeze since it was proposed in last year's budget.
But modelling published in the study shows the freeze would leave doctors worse off by $8.43 per consultation by 2017-18.
Current rules on the rebate prevent GPs using bulk-billing if they do charge a co-payment, but Ms Ley has previously indicated the government may consider changing that.
The study, using the Uni-versity of Sydney's Bettering the Evaluation and Care of Health data, showed freezing the rebate to 2017-18, effectively cut doctors' earnings by 7.1% for every patient they saw.
Co-authors of the study from the university wrote on The Conversation public debate had focussed on the co-payment to date, but not the impact of the rebate freeze.
They wrote it was also likely doctors would charge more than the $8.43 shortfall to cover administrative costs, bad debt, past freezes on rebate increases and potential "lost income".
The Rural Doctors Association and Australian Medical Association have also indicated some GPs may be forced to charge extra to cover their costs of the freeze.
The two GP organisations have also indicated the freeze was exacerbating the ability of doctors to remain viable as businesses, particularly in regional areas.
Ms Ley has indicated the government would not propose any new policies on funding Medicare until it completed its health ind-ustry consultation.
She has said the government would need to reduce health spending over the long term, without detailing the exact measures it would pursue savings through in the coming May budget.