Research has shown that many clinicians lack formal training in evaluating medical decision-making capacity. Typically, patients who may lack capacity are evaluated only when decisions to be made are complex and have significant risks or if patients disagree with physician recommendations. The standards for medical decision-making capacity vary, but require patients to have the ability to:

1) Understand relevant information about proposed diagnostic tests or treatment.
2) Appreciate their situation.
3) Use reason to make decisions.
4) Communicate their choice.

“All licensed physicians can make a determination of incapacity, but most lack the training, experience, and confidence to do so,” says Laura L. Sessums, JD, MD. “Capacity evaluations could benefit from utilizing a standardized approach. Physicians may perform these evaluations more frequently if they have a useful instrument to guide these assessments.”

Intriguing New Research on Capacity

Ideally, clinical tools for evaluating capacity should be brief, reliable, and facilitate the documentation of capacity abilities. Many instruments have been developed for assessing capacity to make medical decisions, but most have not been validated in high-quality studies. In the July 27, 2011 JAMA, Dr. Sessums and colleagues conducted a study to determine the prevalence of incapacity and assess the utility of available instruments for capacity evaluation in adult medicine patients without severe mental illnesses. “Our goal was to provide a guide for clinicians to select a valid, reliable, and clinically useful tool for assessing and documenting incapacity in their own patients,” she says.

The analysis showed that the overall prevalence of incapacity among healthy older adults was 2.8%, but the rate of incapacity increased substantially with higher degrees of morbidity (Table 1). Notably, about one-fourth of medicine inpatients lacked capacity for medical decision making (see also, Improving Boomeratric Care Services). The study also indicated that physicians frequently fail to recognize incapacity among their patients, identifying it in just 42% of cases. However, physicians were usually correct when making the diagnosis of incapacity. “The consequences of patients who lack medical decision-making capacity making their own medical decisions can be significant for patients and physicians,” says Dr. Sessums. “Patients who lack capacity cannot give informed consent for medical decisions.”

Reviewing Capacity Tools

The study by Dr. Sessums and colleagues also reviewed several instruments to assess capacity in routine practice, including the Aid to Capacity Evaluation (ACE), the Hopkins Competency Assessment Test (HCAT), and the Understanding Treatment Disclosure (UTD) test (Table 2). The use of such validated instruments can help physicians better identify patients with incapacity. According to the JAMA study, ACE was a superior instrument for practical use by physicians because it was compared with a gold standard in a clinical trial, has robust test characteristics, and is relatively easy to use. “Perhaps most importantly, ACE uses the medical decision at hand to determine patients’ capacity for decision making,” Dr. Sessums adds. “It’s also available for free online, includes training materials, and takes less than 30 minutes to complete.”

The HCAT and UTD tests were also considered somewhat helpful in assessing patient capacity but were judged to be less useful. The UTD test also fails to measure all capacity abilities.

Optimizing Decision Making

Medical conditions that may be contributing to incapacity should be sought and treated (see also, An Innovative Model for Dementia Care). Furthermore, appropriate communication is critical to the process of capacity assessment. “To evaluate capacity for a particular medical decision, patients must be informed of the nature of the proposed intervention and its purpose, as well as the benefits, risks, and alternatives to proposed interventions, including no action,” says Dr. Sessums. “Increased efforts are needed to optimize and simplify information provided to patients. We need to use plain, jargon-free language and limit the information given before we have patients demonstrate recall of the information they receive. Handouts, graphics, and other visual aids can help patients understand the information given and fortify their capacity for decision making.”

Patients are presumed to have capacity unless proven otherwise. In cases for which physicians are unsure about the diagnosis of incapacity or feel their relationship with the patient may make it difficult for patients to perform their best during the evaluation, Dr. Sessums recommends referral to an expert. “If patients are found to lack capacity and others are in charge of the decision, we should remember to include the patient in discussions about all medical decisions,” she adds. “The phrase ‘nothing about me without me’ applies to such cases.”