A test method is provided for determining whether a person is a schizophrenic, which comprises suitably treating a plurality of test animals, obtaining a sample of the person's blood, pre-mixing the blood, or preferably the plasma therefrom with 3,4-dimethoxyphenylethylamine, internally administering the mixture to the test animals, and maintaining the animals under aggregated or crowded conditions while observing their behavior for amphetamine-like reaction and lethality as an indication of the presence of schizophrenia in the blood sample donor.
