Schizophrenia Spectrum and Other Psychotic Disorders

Considered to be one of the schizophrenia spectrum disorders, schizotypal personality disorder is listed in this chapter. Delusional disorder is the least disabling of the schizophrenia spectrum disorders, and involves the presence of one or more delusions of at least one-month duration. Delusions, hallucinations, or disorganized speech that have a sudden onset and return to normal within a month are indicative of a brief psychotic disorder. Schizophreniform disorder is an intermediate diagnosis between brief psychotic disorder and schizophrenia. Another important distinction separates schizophreniform disorder from a diagnosis of schizophrenia—level of impairment. Symptoms of schizophrenia are the same as for schizophreniform disorder, except for the duration criteria, which must last at least 6 months. Schizoaffective disorder is one of the least understood disorders in DSM-5 . It includes symptoms of a mood disorder along with symptoms of a cognitive disorder, with the duration and severity of each being crucial for diagnosis.