I believe that symptoms are a good blue to gerd but i think that egd
, and posibly oh probe are the best way to characterize the degree of reflux
and severity of damages.
I would add to that an UGI and gastric emptying. The symptoms of gerd can be due to several conditions. If one just uses symptoms as the diagnostic tool, i would not treat medically for longer than 4 weeks. It can be serious.