Document by Department of Health Mental Health Act 2016, Queensland Government on Capacity Assessment for Adults, is a good read and a reference checklist.
This form is an aid to documenting capacity to make decisions related to mental health treatment ONLY. It does not replace any other capacity assessment for other matters or decisions. An assessment for the presence of a mental illness needs to occur prior to this capacity assessment to determine the need for treatment.
The document can be downloaded here (Capacity Assessment for Mental Health Treatment – Adults) or can be viewed below