How Do I Determine if My Patient has Decision-Making Capacity?

It is not necessary to perform a formal assessment of capacity on every inpatient. For most, there is no reasonable concern for impaired capacity, obviating the need for formal testing. Likewise, in patients who clearly lack capacity, such as those with end-stage dementia or established guardians, formal reassessment usually is not required. Formal testing is most useful in situations in which capacity is unclear, disagreement amongst surrogate decision-makers exists, or judicial involvement is anticipated.

The MacCAT-T has been validated in the broadest population and is probably the most clinically useful tool currently available. The MMSE is an attractive alternative because of its widespread use and familiarity; however, it is imprecise with scores from 17 to 23, limiting its applicability.

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Table 2. Components of Capacity Assessments

At a minimum, familiarity with the core legal standards of capacity (communication of choice, understanding, appreciation, and reasoning) will improve a hospitalist’s ability to identify patients who lack capacity. Understanding and applying the defined markers most often provides a sufficient capacity evaluation in itself. As capacity is not static, the decision usually requires more than one assessment.

Equally, deciding that a patient lacks capacity is not an end in itself, and the underlying cause should be addressed. Certain factors, such as infection, medication, time of day, and relationship with the clinician doing the assessment, can affect a patient’s capacity. These should be addressed through treatment, education, and social support whenever possible in order to optimize a patient’s performance during the capacity evaluation. If the decision can be delayed until a time when the patient can regain capacity, this should be done in order to maximize the patient’s autonomy.¹¹

Risk-related standards of capacity.

Although some question the notion, given our desire to facilitate management beneficial to the patient, the general consensus is that we have a lower threshold for capacity for consent to treatments that are low-risk and high-benefit.^12,13 We would then have a somewhat higher threshold for capacity to refuse that same treatment. Stemming from a desire to protect patients from harm, we have a relatively higher threshold for capacity to make decisions regarding high-risk, low-benefit treatments. For the remainder of cases (low risk/low benefit; high risk/high benefit), as well as treatments that significantly impact a patient’s lifestyle (e.g. dialysis, amputation), we have a low capacity to let patients decide for themselves.^11,14

Other considerations.

Clinicians should be thorough in documenting details in coming to a capacity determination, both as a means to formalize the thought process running through the four determinants of capacity, and in order to document for future reference. Cases in which it could be reasonable to call a consultant for those familiar with the assessment basics include:

• Cases in which a determination of lack of capacity could adversely affect the hospitalist’s relationship with the patient;
• Cases in which the hospitalist lacks the time to properly perform the evaluation;
• Particularly difficult or high-stakes cases (e.g. cases that might involve legal proceedings); and
• Cases in which significant mental illness affects a patient’s capacity.¹¹

Early involvement of potential surrogate decision-makers is wise for patients in whom capacity is questioned, both for obtaining collateral history as well as initiating dialogue as to the patient’s wishes. When a patient is found to lack capacity, resources to utilize to help make a treatment decision include existing advance directives and substitute decision-makers, such as durable power of attorneys (DPOAs) and family members. In those rare cases in which clinicians are unable to reach a consensus about a patient’s capacity, an ethics consult should be considered.