> Many of these studies also rely on rating scales (typically HAMD or even PHQ9 for depression) that are a measure of depressive symptoms but don't in themselves have the power to make a diagnosis.

This is my point again if you read my original post, thank you. :)

I'd go further and say the DSM-V is pretty bad at narrowing down which medication to use for depression. I know so many people on damn SNRIs whose diet is complete trash.