Several. I can think of three off the top of my head, Nancy Cruzan, Robert Wendland, and Patricia White-Bull. I am sure there are more, but who knows how many he diagnoses as PVS? Probably plenty. Doesn't mean he's right, just means he's pre-disposed to the idea. A better question would be how many has he not diagnosed as PVS? Any? Or are they all PVS to him?
Three?