I not sure where to ask this other then directly calling up a university that were doing these studies.

So I was looking up Teenage drinking leading to permanent brain damage articles but they don't say how much drinking specifically the patients were doing, not even a example it's always

"repeated heavy drinking" or "Binge drinking" how much is that?, 4 + standard drinks every weekend?, 4+ standard drinks every third day?.

Anyone know where I could find a answer?