Schizophrenia 99
nia; brief psychotic disorder; delusional diso rder; other specified or  unspecified schizo-
phrenia spectrum and other psychotic diso rder; schizotypal, schizoid, or paranoid
personality disorders; autism spectrum disorder; disorders presenting in childhood with
disorganized speech; attention-deficit/hype ractivity disorder; ob sessive-compulsive dis-
order; posttraumatic stress diso rder; and traumatic brain injury.
Since the diagnostic criteria for schizophreniform disorder and schizophrenia differ
primarily in duration of illness, the discussion of the differential diagnosis of schizophre-
nia also applies to schizophreniform disorder.
Brief psychotic disorder. Schizophreniform disorder differs  in duration from brief psy-
chotic disorder, which has a duration of less than 1 month.
Schizophrenia
Diagnostic Criteria 295.90 (F20.9)
A. Two (or more) of the following, each present for a significant portion of time during a
1-month period (or less if successfully treated). At least one of these must be (1), (2), or (3):
1. Delusions.
2. Hallucinations.
3. Disorganized speech (e.g., frequent derailment or incoherence).
4. Grossly disorganized or catatonic behavior.
5. Negative symptoms (i.e., diminished emotional expression or avolition).
B. For a significant portion of the time since the onset of the disturbance, level of function-
ing in one or more major areas, such as work, interpersonal relations, or self-care, is
markedly below the level achieved prior to the onset (or when the onset is in childhood
or adolescence, there is failure to achieve expected level of interpersonal, academic,
or occupational functioning).