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There's no real way to do this at home, sorry.

As for schizophrenia? You'd need to see a doctor who can not only order a Functional MRI that'll scan your brain while you're awake, but it needs to be a "water scale" scan that will pick up on capillary-scale detail of your brain, basically. In other words, bleeding-edge stuff really.

And actually, there IS a blood test for severe depression. Catch is: it's really only a test to verify that you're openly suicidal at that point. See, if depression goes untreated long enough that you _get to_ suicidal ideation, that also means your _blood platelets_ have sprouted serotonin receptors.

They're really and truly NOT supposed to have those. If serotonin receptors are in your bloodstream it means your blood is scouring your whole body for _ANY_ of that neurotransmitter it can spare, any it can find, to keep the suicidal ideation from being present ALL the time. It means your body has already done _everything_ else it can, in terms of taking the stuff from your peripheral nerves (leaving you with aches and pains) and your digestive system (leaving you with irritable bowel syndrome).

But yeah, there's tests. They just aren't in widespread use even in hospitals yet--some of it is expense, sure, but some of this is that insurance companies find it profitable to spend less money and _keep_ the old trial-and-error approach of the DSM going.

the best way is via a brain scan. the scan shows how the brain is functioning, and they can compare it to people who have had schizophrenia. im not sure it can be detected in a blood test. depression cant be detected!

There are certain functional brain scans

They do try to determine if you simply have a chemical imbalance, yes; but only professional hospital equipment can determine that.

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