I'm very skeptical of this. A common claim that's long been floated around the medical community, most recently in the "evidence-based" medical community, is that if there isn't a hard test for a condition, then it's psychosomatic. It's an arrogant and abusive conclusion that's also ironic: we don't have a diagnostic test to prove it, so the cause is something that also doesn't have a diagnostic test.
You can also call it "Mysterious Answers to Mysterious Questions"[0] -- if the matter seems a mystery, well, then the answer surely must be a mystery as well! I cannot be something simple and comprehensible
