Hello, coming to this thread late, but my mother has just been assessed using ACE-iii and was given a score of 45 and a diagnosis of moderate dementia. Like you I have been looking for some more understanding of what that can tell me about where she is on her journey.
I found this paper
https://onlinelibrary.wiley.com/doi...wDfGUIqeKwOUoHQ2E8ZT2KIiZo9vRlvLMIzW4m7Ieksa9
which told me 2 things:
1) the ACE-iii was designed specifically to be a useful tool to diagnose in the early stages of dementia. It's an excellent guide to whether someone is developing dementia or not, but there is no basis established for using it to differentiate between the stages of dementia. The MMSE is used for this
2) This paper suggests 'a cutoff point of 61 on the ACE-III is sensitive for distinguishing mild dementia from moderate dementia' but that it requires further study.
I hope this might be useful for you, I hope you and your Mum are both doing okay.