DSM Criteria for Schizophrenia

Here are the diagnostic criteria for schizophrenia from DSM–IV (Diagnostic and Statistical Manual of Mental Disorders, 4th edn, copyright 1994, American Psychiatric Association): A Characteristic symptoms: two (or more) of the following, each present for a significant portion of time during a one-month period (or less if successfully treated): 1 delusions 2 hallucinations 3 disorganised speech (for example, frequent derailment or incoherence) 4 grossly disorganised or catatonic behaviour 5 negative symptoms, for example, affective flattening, alogia, or avolition. Note: only one criterion of a symptom is required if delusions are bizarre or hallucinations consist of a voice keeping up a running commentary on the person’s behaviour or thoughts, or two or more voices conversing with each other. B Social or occupational dysfunction: for a significant portion of the time since the onset of the disturbance, one or more major areas are functioning such that work, interpersonal relations, or self- care are markedly below the level achieved prior to 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 six months. This six-month period must include at least one month of symptoms (or less if successfully treated) that meet criterion A (that is, active phase symptoms), and may include periods of prodromal or residual symptoms. During these prodromal or residual periods, the signs of the disturbance may be manifested by only negative symptoms, or two or more symptoms listed in criterion A in an attenuated form (that is, odd beliefs, unusual perceptual experiences). D Schizoaffective and mood disorder exclusion: schizoaffective disorder and mood disorders with psychotic features have been ruled out, either because: 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. The diagnosis of schizophrenia in DSM–IV can be further classified on the basis of its course (that is, episodic, continuous, in partial or full remission, and with or without negative symptoms) or subtype. The subtypes of schizophrenia are defined by the predominant symptom pattern at the time of evaluation. The subtypes of schizophrenia include paranoid type, disorganised type, catatonic type, undifferentiated type, and residual type. The prognostic and treatment implications of the different subtypes are very variable, and in clinical practice the distinctions between the different subtypes are not often used. In the recent revision of the DSM (DSM-V) the note at the base of A is deleted (this gave extra weight to bizarre delusions and to ‘first-rank’ auditory hallucinations - a running commentary on the person’s behaviour or thoughts, or two or more voices conversing with each other), and it is now required that a person must now have at least two of the three ‘positve’ symptoms (hallucinations, delusions and disorganised speech). Schizophrenia subtypes have also been removed. It is not yet clear how influential the revised DSM will be in Australia.