[MacCAT-T between Claim and Practice - Challenges of Assessing Capacity for Consent in Dementia].

Background: Consent is a prerequisite for medical diagnostic and therapeutic action. There is no standardised procedure for assessing the ability to give consent. The most widely used tool for structured assessment is the MacArthur Competence Assessment Tool for Treatment (MacCAT-T).

Objectives:  People with dementia have impaired capacity to consent because of their disease. In order to answer the question to what extent structured assessment procedures can be usefully applied to people with dementia, we analyse the function, strengths and weaknesses of structured assessment procedures with a focus on the MacCAT-T and discuss suggestions for modification and further development of the tool.

Methods: Using the PubMed literature database, a systematic literature search and analysis was conducted on papers published since 2010, following PRISMA guidelines.Results Although the MacCAT-T is a valid and reliable tool, it cannot comprehensively address memory problems in people with dementia. It primarily measures cognitive functions. However, Decisions based on emotions, intuitions and values, are not captured by the MacCAT-T. Communicative limitations in people with dementia are not taken into account.

Conclusions:  It is recommended to provide information in simple language, written down and visualised for people with dementia. The development and elaboration of a graduated procedure for the examination of capacity to consent is indicated. The gradations of the scope and depth of the assessment to be determined should be based on the severity of the cognitive impairment, the benefit/risk ratio of the proposed medical intervention and the individual profile of affective functions and value-based imprints.