Queensland Deputy State Coroner Stephanie Gallagher on Thursday handed down her findings following an inquest into Joshua's death and his treatment while in mental health and emergency room care.

About a month before his death, Joshua had quit his heavy use of cannabis as it had threatened his ability to work as an apprentice painter.

During his medically assisted detox period, Joshua had attended hospital with complaints of having "crazy" thoughts and feeling depressed.

Ms Gallagher found it was appropriate for Queensland Health's Child and Youth Mental Health Services to close their file on Joshua in February 2017 as he was moving to private care.

However, Ms Gallagher accepted a submission from Joshua's family that youth mental health services did not prepare a formal transfer of care plan to provide additional information to his private carers.

The inquest noted that Gold Coast Hospital and Health Service had completed a review after Joshua's death and did not identify any root causes or contributory factors.

The review, which included an interview with Joshua's family, did identify opportunities for improvement around mental health engagement with children and their families and how staff could intervene in a crisis.

The health service is also reviewing its emergency department environment to provide spaces for people with sensory overload, which is a common symptom of autism spectrum disorder.

Ms Gallagher found there were "no appropriate comments or recommendations" she could make given the review and improvement steps taken by the health service.

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