Just 14 per cent of the population has an Advance Directive, or "living will", detailing their end of life treatment and care preferences, according to an article led by QUT Australian Centre for Health Law Research director Professor Ben White.
This research is from a joint University of Queensland, QUT and Victoria University study, supported by the Australian Research Council in partnership with seven public trustee organisations across Australia.
An Advance Directive is a legal document in which a person specifies what treatment or end of life care they want, when they no longer have the capacity to decide.
"There are ongoing calls from government, academics and policy-makers to improve how we die and how we can have a 'good' death," Professor White, whose research has been published in the Internal Medicine Journal, said.
"Advance care planning is usually at the forefront of these policy discussions so when a person loses capacity, those responsible for that person's care knows what they would want."
Professor White said having an Advance Directive was important because it offered those who are dying the chance to have their wishes about end of life care respected.
"Our findings present an opportunity, outside the health setting, to advance the policy goal of increasing advance care planning," he said.
"Those responsible for advising wider future planning processes such as will-making, including lawyers and financial planners, should be co-opted into efforts to encourage people to plan not only for their financial future but for their health as well.
"And health professionals must take opportunities to inquire about people's existing directives. Getting Australians to think about advance care planning is a big challenge, so we need to think about how to start conversations about future health decision-making."
The survey results, which include the first national data on the prevalence of Advance Directive completion in Australia, revealed wide variations from state to state with South Australia (21 per cent) and Queensland (19 per cent) leading the country for the number of residents with Advance Directives.
The Northern Territory had the lowest number of people with an Advance Directive (9 per cent).
"Australians are far more likely to make a will (59 per cent) or an enduring financial power of attorney (30 per cent) than an Advance Directive," Professor White said.
"But interestingly, there is a clear association between those people who have prepared a will or a financial enduring power of attorney and those people who have completed an Advance Directive.
"We found that people who completed a financial enduring power of attorney were nine times more likely to have an Advance Directive than those who hadn't, while those with a will were 2.5 times more likely to have an Advance Directive than those without."