How do you determine if a person is competent to make medical decisions or if a power of attorney (POA) is needed?

Determining Medical Decision-Making Capacity vs. Need for Power of Attorney

To determine if a person is competent to make medical decisions or if a power of attorney (POA) is needed, you must assess the patient's decision-making capacity using a structured approach that evaluates four key abilities: understanding, appreciation, reasoning, and communication of choice. 1

Assessment of Decision-Making Capacity

Step 1: Evaluate the Four Core Abilities

• Understanding: Ask the patient to explain in their own words:

  • Their medical condition
  • The proposed treatment or intervention
  • Alternative options
  • Risks and benefits of each option 1, 2

• Appreciation: Determine if the patient:

  • Acknowledges their medical condition
  • Recognizes the consequences of treatment options
  • Applies the information to their personal situation 1, 2

• Reasoning: Evaluate the patient's ability to:

  • Compare options using personal values
  • Provide logical reasons for their choice
  • Demonstrate consistent reasoning 1, 2

• Communication: Verify the patient can:

  • Express a choice clearly
  • Maintain consistency in their decision 1, 3

Step 2: Consider Decision Complexity and Context

• Capacity is decision-specific - patients may have capacity for simple decisions but not complex ones 1, 2
• The assessment should be proportionate to the risks involved in the decision 1
• Timing matters - assess capacity when the decision needs to be made, as capacity may fluctuate 2, 1

When a Power of Attorney Is Needed

A power of attorney becomes necessary when:

1. The patient fails to demonstrate the four abilities listed above 2
2. The patient cannot understand and retain information about their condition and care options 1
3. The patient cannot weigh information as part of the decision-making process 1
4. The patient cannot communicate their decision 1

Important Considerations

• Presumption of Capacity: Adults are presumed to have decision-making capacity until demonstrated otherwise 1
• Diagnosis Is Not Determinative: A diagnosis of dementia or psychiatric illness does not automatically mean lack of capacity 1
• Unwise Decisions: A patient should not be deemed incapable merely because they make a decision that appears unwise to clinicians 1
• Support First: Patients cannot be treated as lacking capacity unless all practicable steps to support them have been taken without success 1
• Documentation: Document your assessment thoroughly, including specific questions asked and the patient's responses 3

When Capacity Is Questionable

Consider formal capacity evaluation when:

• The patient has an acute change in mental status
• The patient refuses clearly beneficial treatment
• The patient readily agrees to a risky procedure without consideration
• There are risk factors for impaired decision making 3

For Patients Without Capacity

If a patient lacks capacity:

1. Identify an appropriate surrogate decision-maker according to your jurisdiction's laws 1
2. For previously competent adults, decisions should align with:
   • Previously stated treatment preferences
   • What the patient would likely choose if able (substituted judgment)
   • The patient's best interests 1
3. In some jurisdictions, if no advance directive exists, a "default" surrogate is empowered in this order: spouse, adult child, parent, sibling, or friend 2

Pitfalls to Avoid

• Relying solely on physical status or cognitive screening tests for capacity assessment 1
• Making sweeping determinations about a person's overall competence 2, 1
• Failing to reassess capacity, as it may fluctuate, especially in patients with dementia 2, 1
• Obtaining surrogate consent without making every effort to obtain the patient's own consent first 2

By following this structured approach, you can appropriately determine when a patient has capacity to make their own medical decisions and when a power of attorney is needed to protect their best interests.