I don't have a source for getting an official definition. But I will note this:
Signal 46 is normally used by PD or DFR where an individual has possible mental health issues.
"Right Care" is a joint group between Dallas PD, Dallas Fire Rescue, and the Parkland Health system.
See this article from D-Magazine:
When it comes to mental health intervention, the city and county have found a way to collaborate and thrive.
www.dmagazine.com
If you search "Right Care", you will find other articles concerning this.
There are several other 46-CIT calls active on Open Data, in other areas, but the in the Northwest Patrol Division is the only one flagged as 'Right Care'.
The address of that call, 5300 Harry Hines, is the location of one of the buildings used by UTSW. Whether that is where the subject was first encountered, or it is merely a coincidence, I have no way of knowing.