- (Choice) The ability to express or communicate one’s choice
- (Understanding) The understanding of the facts involved in that decision
- (Appreciation) A genuinely belief that the information truly applies to them
- (Reasoning) The ability to derive consistent conclusions from premises, to weigh risks and benefits and evaluate putative consequences
However, the problem is that there are cases in which patients do acquire those 4 abilities, but still seem to not have sufficient decisional capacity. For example, to quote a patient with anorexia nervosa (who seems to have those 4 abilities):
Although I didn’t mind dying, I really didn’t want to, it’s just I wanted to lose weight, that was the main thing.
Here is one explanation on how to assess whether such patients have decisional capacity or not (emphasis mine):
Hope et al. (2013) have argued that individuals with anorexia are in the grip of affective states that shape how they see the world. Yet, although the world presents to them as one way, they may at another more reflective level, reject the appearances. Thus an individual may have a strong feeling or emotional sense that she is fat. But even though these feelings incline her to accept the proposition that she is fat she may not in fact believe at a higher level that she is fat. She may know quite well that she is dangerously thin. An analogy here with optical illusions is helpful. The experience of seeing a stick in water as bent is incredibly powerful, but we may nonetheless know it is not bent. However, the mental state that is most authoritative when it comes to reporting our beliefs may not be the same as the mental state that is most motivationally powerful. When it comes time to make choices about treatment, the salience of the affective phenomena and the relative lack of salience of the dangers of self-starvation may lead a person to refuse treatment.
In order word, that patient seems to be announced as not having decision-making capacity, and thus may be fed by force.
However, isn't this the same with addiction or fear? For example, a smoker who acknowledge its harm, or a patient who refuses to be helped because they have incorrect or maladaptive beliefs, which based on past traumas. For example, a smoker can say a similar statement:
Although I didn’t mind dying, I really didn’t want to, it’s just I wanted to smoke so bad, that was the main thing.
In those cases, would we say that they are not having sufficient decisional capacity, and thus it is allowed to force them into treatment? How do addiction and fear affect patient's decisional-making capacity?
Note: One of the expectation for an ethical theory of decision-making capacity is All-or-nothing assessment: "To avoid potentially endless controversy and ensure the smooth operation of the healthcare system, law and practice need a “yes-or-no” verdict about whether a person can make a particular decision for herself or not." I suppose that this is irrelevant at best, and an skewing condition at worst, for a psychological theory of decision-making process.
I live in Vietnam, but I don't think it much matters.