According to DSM-IV,
the catatonic subtype was to be diagnosed even when the person
had symptoms of the paranoid and disorganized subtypes; the disorganized
subtype was to be diagnosed even when the person had
symptoms of the paranoid subtype; and the undifferentiated subtype was to be diagnosed only when the person failed to have symptoms
of the catatonic, disorganized, or paranoid subtypes. Despite the
introduction of a subtyping hierarchy in DSM-IV with the catatonic
and disorganized subtypes at the apex of the hierarchy, these subtypes
are still very rarely diagnosed. Administrative psychiatric practice
data in the USA reveal that the catatonic subtype is applied to just
1% of all Medicaid recipients and 2% of general outpatients with a
diagnosis of schizophrenia