As the global community recognises World Suicide Prevention Day, researchers have called into question the reliability of Australia's suicide statistics.

Suicide is a global public health problem and the leading cause of death amongst young adolescent Australians, and yet two Australian scholars now suggest that Australian Bureau of Statistics (ABS) suicide data may be flawed, painting an incorrect picture of the nation's mental health status.

Dr Samara McPhedran from the University of Sydney and her colleague Dr Jeanine Baker from South Australia, reviewed ABS technical notes and found that open coroner's cases have increased in recent years, leading to unintentional deaths being 'over-counted' and suicides being 'under-counted'.

The findings, which appear in the respected international journal Public Health, also suggest unintentional firearm-related deaths may be lower than thought, but raise concerns that suicides could be higher than ABS data indicate.

"Last year we found that the pre-existing downward trend in firearm suicides accelerated after the 1996 gun laws, but unintentional deaths increased. This seemed strange, so we took a closer look at the numbers," said Dr McPhedran.

"Data inaccuracies would affect the overall picture of Australian suicide levels, not just records of firearm-related deaths. This has serious implications, because many evaluations of suicide prevention strategies in Australia use ABS data," she said.

The researchers say that effective public health initiatives need to be built on accurate information. "Basing policy on the wrong information is like building a house of straw and expecting it to withstand a gale," said Dr McPhedran

"For example independent work shows ABS data 'under-counted' the total number of suicides (all methods) in Queensland by 127 cases, in 2004 alone," she said.

The authors go on to recommend crosschecking ABS data against coronial records and revision where necessary.