The dominant approaches to assessing patients for decisional capacity in the clinical setting, the "four skills" and "sliding scale" models, emerged in the 1970s and 1980s against a backdrop of medical paternalism and reflect their origins in law and forensic psychiatry. They privilege rationality and require the ability to defend one's decisions with knowledge and argument. Unfortunately, these approaches place a heavy burden upon patients who may hold preferences consistent with their underlying values but may not possess the education or reasoning skills necessary to meet the heavy burden imposed by current capacity standards. This article reviews the shortcomings of the dominant models. Then the article proposes a novel value-based approach to capacity assessment that places primary emphasis upon the patient's underlying and longstanding values and the concordance of those values with the patient's current wishes and preferences.
Keywords: capacity; competence; mental health ethics; psychiatry; sliding scale.