My experience from my coursework was that the cited studies seemed to me to be pretty rigorous. There was an entire section dedicated to what might have been titled "junk science", though as I recall the authors of the textbook used a somewhat more diplomatic term. In there were all kinds of commonly-held disorders like pre-menstrual syndrome, seasonal affective disorder in the like where research suggests that while the disorders may be real, they in fact effect a far smaller group of people than earlier studies had claimed. In other words, even in psychology it sure looks to me like there is at least some psychologists who follow valid methodological principles.
The other thing to remember is that "psychology" is a pretty damned broad term, and that in a lot of cases other professions like psychoanalysts, psychiatrists, counselors and the like often get lumped in, and in some cases these other groups publish in journals of varying degrees of quality. That's not to say that some of these people don't adhere to pretty strong methodologies, but it does tend to be a bit of a wild west in some cases. But when you're talking about cognitive psychology and other similar branches, there's a lot of overlap there that pulls in neurological experts, behavioral experts and the like who sit within the harder edges of the psychology field. It most certainly isn't all just kooky neo-Freudians.