There may be more than one cause of a cat litter box problem, but they come from one of two categories. If you’ve read my article on the physical causes of this dilemma, then you already know that this problem is either physical, or behavioral.
Since your cat can’t tell you what’s going on, you have to rule out each possible cause, until you are left with the most logical answer. This is known as a diagnosis of exclusion.
You’ll need help from your vet on this one, since you’ll want to first rule out any physical cause. It’s always best to assume your cat has a physical problem until your vet proves you wrong.