The research is based on adolescents' survey responses to questions about self-injury when they were aged 14-15 and again at age 16-17 as part of Growing Up in Australia: The Longitudinal Study of Australian Children (LSAC). One of the report's authors, Dr Pilar Rioseco says the findings are concerning, especially in light of emerging signs of worsening mental health in the pandemic.

We saw thoughts and acts of self-injury increase as adolescents became older. At age 14-15,16.4% of adolescents had thoughts of self-injury and 9.7% reported acts of self-injury. This rose to 21.2% for thoughts and 11.2% for acts by age 16-17" said Dr Rioseco.

"Navigating your way through the world as a young person can be challenging and it's clear that managing self-injury thoughts and behaviours is a critical aspect of adolescent health care provision," said Dr Rioseco.

The study found that when it came to thoughts and acts of non-suicidal self-injury, there were considerable gender differences. Close to half (42%) of girls reported thinking about self-injuring at 14-15 or 16-17, compared to 18% of boys. Similarly, 26% of girls reported acts of self-injury at either 14-15 or 16-17, compared to 9% of boys.

Girls were also more likely to engage in repeated self-injury. Around 7% of girls reported self-injury at both ages 14-15 and 16-17, compared to 1% of boys. Concerningly, repeated self-injury over time was strongly associated with suicidal behaviour; 65% of those who engaged in repeated self-injury reported attempting suicide at age 16-17.

"While both genders are experiencing high rates of self-injury thoughts and behaviours, it is alarming to see how much more common it is among girls," Dr Rioseco said.

The report also examined some risk and protective factors for adolescent self-injury. It showed that those who were same-sex attracted at age 14-15 (lesbian, gay or bisexual) were more likely to report having self- injured at some point between the ages of 14 and 17, compared to those who were not same-sex attracted (heterosexual, unsure or no attraction: 55% vs 15%). They were also more likely to engage in repeated self-injury (22% vs 3%, respectively).

"As a same-sex attracted person, you are potentially living with the stress of being a stigmatised minority. Despite progress over the last few years, same-sex attracted adolescents may still find they have to contend with harassment, discrimination and bias from family, peers and schools," said Dr Rioseco.

"These attitudes can become internalised, exacerbating what is already a stressful time for some young people and increasing the risk of self-injury thoughts and behaviours," said Dr Rioseco.

The report found that having a close relationship with a parent was protective against self-injuring, while poor parent mental health in early childhood is a risk for adolescent self-injury several years later.

"It's essential that parents, caregivers and schools are equipped with the right skillset and provided with the support they need to assist adolescents throughout this time," said Dr Rioseco.

"Ultimately, self-injury thoughts and behaviours need to be seen for what they are - a response to mounting stress and a way of relieving emotional pain,"

"There's an urgent need for integrated care involving families, schools, and communities to enhance safety among these distressed young people in both the short and long term," Dr Rioseco said.

Access the report: Self-injury among adolescents.

Growing Up in Australia: The Longitudinal Study of Australian Children (LSAC) is an ongoing, nationally representative study that follows the lives of children and their families from all over Australia.

In 2004, around 5,000 0-1 year olds (B cohort) and 5,000 4-5 year olds (K cohort) and their families were recruited and have been surveyed every two years since. With extensive information on children's physical, socio-emotional, cognitive and behavioural development and linked biomarkers, education, health and welfare data, the study has been a unique resource providing evidence for policy makers to identify opportunities for early intervention and prevention strategies.

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