New Zealand's suicide rate is higher than Australia's; twice as many of our young men have killed themselves in recent years.
A study published in the New Zealand Medical Journal compared suicide rates between the nations from 1949 to 2013, focusing on age patterns.
In the latest year bracket available, 2009 to 2013, the rate among Kiwi men aged 20 to 24 was 29.7 per 100,000 - double the rate of Australian men of the same age group.
The study, "Changes in the age pattern of New Zealand suicide rates'', by Australian clinical professor John Snowdon, was based on Ministry of Health and Australian Bureau of Statistics data and census data.
While suicide rates were similar between the nations generally, New Zealand's rate was higher overall, due to higher rates among young citizens, including a "markedly higher'' suicide rate of youths.
New Zealand has continuously ranked among the worst in the world for levels of teen suicide.
An OECD report published last year found New Zealand had the highest rate in the developed world.
"There must be continued concern regarding the relatively high youth suicide rate in New Zealand versus the much lower corresponding rates in Australia,'' Prof Snowdon said.
He proposed substance abuse could be a factor in the rise and fall of suicide rates of young adult males.
As well as age patterns, Prof Snowdon also compared suicide rates among Maori and non-Maori with Aboriginals and non-Aboriginals.
The suicide rates of young adult indigenous populations in both countries remained high, but there was a fall in the suicide rate of non-indigenous youths in Australia.
"Suicide appears to be especially a problem among Maori youth,'' Prof Snowden said.
The study noted explanations that had been made for the high Maori youth suicide rate, including the disadvantaged status of Maori in society, cultural alienation and confusion over identity.
"It was also suggested that Maori, who traditionally identify themselves as members of a collective group, may find difficulty in societies which value individualism.''
There have been substantial decreases in the suicide rates of New Zealanders and Australians over 55 since the 1980s.
The study suggested this could be due to multiple factors, including greater use of antidepressants and the increased attention to the health and welfare needs of elderly people.
Where to get help:
• Lifeline 0800 543 354 or 09 522 2999
• Suicide Prevention Helpline 0508 828 865 (0508 TAUTOK0)
• Youthline 0800 376 633 or free text 234
• Samaritans 0800 726 666
• If it is an emergency and you feel like you or someone else is at risk, call 111.
