More than two-thirds of young people who die from suicide in Australia are not receiving mental health treatment around the time of their deaths, according to a study of coronial records.

Researchers scoured more than 3000 coronial inquiries into suicides by people aged 10-24 between 2006 and 2015 in the first nationwide investigation of its kind.

They found just 40% of the young people had confirmed mental health diagnoses, most commonly depression, while another 16% were described as having possible mental health disorders, based on the coroner’s subsequent investigation.

While 80% of people with a diagnosis were being treated, because so few people had a formal diagnosis, the overall rate of mental health treatment was only 33%.