Mental capacity assessments are conducted in order to evaluate someone’s ability to make particular decisions or perform certain functions. Within the practice of Psychiatry, these decisions are generally in regard to choosing between medical treatment options, facility placement, or being placed under guardianship or conservatorship, but can also involve financial decisions such as drafting or changing a will (testamentary capacity), assigning a power of attorney, and whether someone may be vulnerable to undue influence.

Throughout the United States adults are assumed to have various decision making capacities unless they are demonstrating otherwise. Widely accepted legal framework for whether someone retains a particular decision-making capacity relies on that person exhibiting their ability to:

1. 1. Communicate a choice in regard to what is being proposed
   2. Understand what is being proposed
   3. Understand potential consequences of the decisions they may make in regard to what is being proposed
   4. Rationally manipulate information pertinent to what is being proposed

Capacity evaluations may only be considered valid in regard to a specific question or circumstance, and at a specific time, and generally should not be broadly applied. However, when someone is suffering a long term disability such as dementia, intellectual disability, or traumatic brain injury, it may be appropriate out of abundance of caution for their safety to assess more broadly for their capacity to make autonomous decisions related to safety and self-care.

Determining whether someone exhibits decision making capacity is a core feature of the informed consent process that takes place countless times every day during the practice of medicine. It should be revisited regularly for those with cognitive impairments or significant risk factors for development of cognitive impairments.

There may be situations in which determining the fourth criteria listed above is not clear, requiring formal evaluation by a specialist trained in capacity assessments. This is commonly done for testamentary capacity assessments.

Mental