FIM scores at the extreme low or high range correspond well with discharge disposition (low scores more likely to be discharged to a facility, high scores more likely to be discharged home). The article linked below explains that individuals scoring less than 40 on the FIM have a 70% probability of being discharged to a skilled nursing facility.
https://onlinelibrary.wiley.com/doi/full/10.1002/j.2048-7940.2006.tb00006.x
Hope this helps!
Chrissy