Initial review time in ticket

Hello,

I need to know how can I get the initial review time by agent in a ticket, I mean if there is a ticket created yesterday for example at 13:00 and the initial review SLA defined is 5 minutes, but the processor is assign until today at 14:00 and he changed the status from “open” to “In process” in 7 minutes.

I know the initial review were not accomplish because it takes more than 5 minutes, but I need to know the real inicial review time by the agent I mean the 7 minutes. 

Is there a data source that I can to use to find this initial review by agent? Or some tip that can you give me to find this value? 

Please let me know. 



Best Regards,
Jorge Jimenez