Wireless (WiFi) MOS equivalent?

Hello all, Is there a WiFi equivalent to the VoIP MOS score? We are looking for a way to measure performance of a fairly large WiFi deployment. We have 8000+ access points (All Cisco). WE have the standard Cisco tools for managing the wireless network (ISE, Prime etc). But we are coming up short with a way to “score” the network. Does anyone have experience with this that might be able to help? How do large conferences “measure” wireless service quality etc? We are already doing end user surveys etc. We have “soft date”, we really need data points. —Jim