Schizophrenia can be defined as "a disorder with a range of symptoms involving disturbances in content of thought, form of thought, perception, affect, sense of self, motivation, behavior, and interpersonal functioning" (Halgin 514). Childhood-onset schizophrenia is a rare disorder that can be diagnosed using the same diagnostic criteria that is used with adult-onset cases, but patients must have an "onset of psychotic symptoms by age 12 years" (Kumra). While 0.5% of the adult population in the United States has schizophrenia, there are 50 times fewer cases in children under the age of 15 (Clark 1072).
The Diagnostic and Statistical Manual of Mental Disorders, 4th edition, defines the characteristics of Schizophrenia that are used as diagnostic criteria. To be diagnosed with Schizophrenia, one must display 2 or more of the following for at least one month: delusions, hallucinations, disorganized speech, disorganized or catatonic behavior, and negative symptoms (First 285). The hallucinations and delusions that children experience are usually much less complex than those of adults, and thought interference is not usually expressed in children as it is in adults (Clark 1072). In order to be diagnosed, one must also have a social and/or occupational dysfunction, have continuous signs of schizophrenia for at least 6 months, and have ruled out other possible diagnoses such as Schizoaffective and Mood disorders, substance abuse, or other medical conditions (First 285-6). There are several different types of schizophrenia, including the Paranoid type, where one is preoccupied with delusions and auditory hallucinations, the Disorganized type, where one has disorganized speck and behavior and inappropriate affect, the Catatonic type, where one could have several symptoms including peculiar voluntary movement, excessive motor activity, and motoric immobility, and Undifferentiated type, where one does not fit into any of the other categories (First 287-9).