Anyone have direct experience dealing with APS in Los Angeles County? Mom is being neglected.

We have enough documentation to demonstrate neglect. We've made calls to all the "right" agencies and people, including mom's doctors and the police. Nothing seems to ever happen. Anyone have any success working with APS in Los Angeles? What can we expect? How long does it take them to respond to complaints? Are they as useless as they seem to be? I'm looking for responses from people that have actually dealt with APS. Many thanks in advance!