Sorry it took so long to reply, I just wrote an essay for Seattle1!
I am a little confused about your question, but I think you are referring to a legal standard some courts use to determine a respondent's decision-making. There are two schools of thought in U.S. jurisprudence. One is the doctrine of substituted consent, the other best-interest.
Substituted consent would make a decision consistent with an individual's wishes. Or what we usually think of as autonomous "intent." What the respondent intended to mean when they conveyed their wishes.
A best-interest standard would require that the guardian look at the pros and cons of the procedure or situation and determine what is in the individual’s best interest.
Hope this is what you were asking, and thanks for the reply!
ETA: I'm not sure which standard Indiana uses. And it's the weekend, so I'm gonna be lazy and not look it up!