Evaluation of the capacity to appoint a healthcare proxy.

The appointment of a healthcare proxy is the most common way through which patients appoint a surrogate decision maker in anticipation of a future time in which they may lack the ability to make medical decisions themselves. In some situations, when a patient has not previously appointed a surrogate decision maker through an advance directive, the healthcare team may ask whether the patient, although lacking the capacity to make a healthcare decision, might still have the capacity to appoint a healthcare proxy. In this article the authors summarize the existing, albeit limited, legal and empirical basis for this capacity and propose a model for assessing capacity to appoint a healthcare proxy that incorporates clinical factors in the context of the risks and benefits specific to surrogate appointment under the law. In particular, it is important to weigh patients' understanding and choice within the context of the risks and benefits of the medical and interpersonal factors. Questions to guide capacity assessment are provided for clinical use and refinement through future research.