Decision-making capacity assessments in New Zealand and Australia: a systematised review

In an ageing world with a growing prevalence of neurodegenerative disease and recent voluntary assisted dying laws in New Zealand and several Australian states, healthcare professionals are increasingly being relied upon to conduct decision-making capacity (DMC) assessments. There is no legislation in New Zealand or Australia to provide clear guidance on conducting DMC assessments. This systematised review aimed to examine the current processes, issues and debates within DMC assessments as detailed in Australasian literature. Six databases were searched: CINAHL, Scopus, Embase, Medline, PsycINFO and Google Scholar following PRISMA guidelines. A total of 33 articles were included in the review and, following a quality assessment, an inductive approach was used to determine key topics which were synthesised in the review. Five distinct issues were revealed, namely a lack of standardisation and guidelines in approaching DMC assessments, training and knowledge of DMC, professional roles, medical and psychiatric complexities and the medico-legal interface.