God is a part of psychiatry, psychology, psychotherapy, psychoanalysis, and all of the other behavioral sciences and behavioral quasisciences because they all include the concept of the theos (see //uspsych.org/2012/06/20/a-theos-is-something-with) and God is one example of a theos.

Whether God is the supreme (best) theos is beyond the scope, arguably (it can be argued both ways), of the mind sciences (behavioral sciences, which include psychiatric science, not psychiatry, and behavioral quasisciences, which include psychiatry).  I will say, in passing, that I believe that God is the supreme theos and I explain at American Theists why I believe this to be the case.