• Negative symptoms include a lack of motivation and social interactions and flat effect. Negative symptoms are most frequent in early childhood and later adolescence. Children with high IQs often show more positive and fewer negative symptoms than children with low IQs.
• Disorganization of thoughts and behavior can cause significant impairment.
• Cognitive impairment is common and is perhaps the most disabling feature of schizophrenia, causing marked social and functional impairment.
A. Characteristic symptoms: two of the following, each present for a significant portion of time during a 1-month period (or less if successfully treated) 1.
2.
3.
Disorganized speech (e.g., frequent derailment or incoherence) 4.
5.
Negative symptoms (i.e., affective flattening, alogia, or avolition)
Note: Only one criterion A symptom is required if delusions are bizarre or hallucinations consist of a voice keeping up a running commentary on the person’s behavior or thoughts or two or more voices conversing with each other.
B. Social/occupational dysfunction: for a significant portion of the time since the onset of the disturbance, major areas of functioning, such as work, interpersonal relations, or self-care, are markedly below the level achieved before the onset (or when the onset is in childhood or adolescence, failure to achieve expected level of interpersonal, academic, or occupational achievement).
C. Duration: continuous signs of the disturbance persist for at least 6 months with at least 1 month of symptoms (or less if successfully treated) that meet criterion A (i.e., active-phase symptoms) and may include periods of prodromal or residual symptoms. During prodromal or residual periods, signs of disturbance may be manifested by only negative symptoms or symptoms listed in criterion A present in an attenuated form (e.g., odd beliefs, unusual perceptual experiences).
D. Schizoaffective and mood disorder exclusion: schizoaffective disorder and mood disorder with psychotic features have been ruled out because either (1) no major depressive, manic, or mixed episodes have occurred concurrently with the active-phase symptoms or (2) if mood episodes have occurred during active-phase symptoms, their total duration has been brief relative to the duration of the active and residual periods.
E. The disturbance is not due to the direct physiologic effects of a drug abuse, a medication, or a general medical condition.
F. If there is a history of autistic disorder or another pervasive developmental disorder, the additional diagnosis of schizophrenia is made only if prominent delusions or hallucinations also are present for at least 1 month (or less if successfully treated).
Classification of longitudinal course (can be applied only after at least 1 year has elapsed since the initial onset of active-phase symptoms):
Episodic with inter-episode residual symptoms (episodes are defined by the reemergence of prominent psychotic symptoms); also specify if: with prominent negative symptoms.
Episodic with no inter-episode residual symptoms
Continuous (prominent psychotic symptoms are present throughout the period of observation); also specify if: with prominent negative symptoms.
There are five subtypes of schizophrenia: paranoid, disorganized, catatonic, undifferentiated, and residual.
Paranoid type: prominent hallucinations and delusions with relatively normal cognition. The delusions are often persecutory, but other types of delusions also may occur.
Disorganized type: disorganized speech, disorganized behavior, and flat or inappropriate affect.
Catatonic type: prominent psychomotor abnormalities that may include extreme inactivity or excessive motor activity. Cataplexy (waxy flexibility) is rare in children and adolescents.
Undifferentiated type: case in which a patient meets the diagnostic criteria for schizophrenia but not paranoid, disorganized, or catatonic type.
Residual type: clinical situation in which full diagnostic criteria have been met previously but no current, prominent, positive symptoms.