Residual type of schizophrenia is codified 295.60 in DSM IV documentation.
The disorder is characterized by the presence of at least one episode of schizophrenia; however, the presenting condition does not include any prominent psychotic symptoms viz. delusions, hallucinations, disorganized speech or disorganized behavior. At the same time, either negative symptoms may be present – such as flat affect, poverty of speech or avolition – or positive symptoms may be present – such as eccentric behavior, mildly disorganized speech or odd beliefs.
When delusions or hallucinations are present in residual type schizophrenia, they are not very prominent, and they are not accompanied by any strong affect. The course of residual type schizophrenia may be time-bound, and the patient may be in a transient phase between complete remission and a full-blown episode. However, the course may last for several years, too, with or without acute exacerbations.