No, there isn't. I gave you the analogy of a woman who, because of a delusion, thinks that she's giving people something to make them better, but it turns out to be poison. As you can see, the consequences of that delusion depend on many other factors, so deciding what to do with that person on the basis of what happened, of how many people took the poison, is really a wrong way to do it.
That's very different from a person who intentionally commits a crime in which what they did is an example of what they're willing to do. In the case of a person who commits a crime because they didn't know that what they were doing was wrong, the dangerousness has to do with whether they can still have the delusion, and not with the brutality of the actual act.