The following are the revised criteria for a diagnosis of schizoaffective disorder from the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR):
- Two (or more) of the following symptoms are present for the majority of a one-month period (or a shorter period of time if symptoms got better with treatment):
- disorganized speech (e.g., frequent derailment or incoherence) which is a manifestation of formal thought disorder
- grossly disorganized behavior (e.g. dressing inappropriately, crying frequently) or catatonic behavior
- negative symptoms—e.g., affective flattening (lack or decline in emotional response), alogia (lack or decline in speech), avolition (lack or decline in motivation), anhedonia (lack or decline in ability to experience pleasure), social withdrawal (sometimes called social anhedonia). Negative symptoms refers to symptoms that are not present or that are diminished in the affected persons but are normally found in healthy persons.
If the delusions are judged to be bizarre, or hallucinations consist of hearing one voice participating in a running commentary of the individual’s actions or of hearing two or more voices conversing with each other, only that symptom is required to meet criterion A above. The speech disorganization criterion is only met if it is severe enough to substantially impair communication. and at some time during the illness there is either one, two or all three of the following:
- During the illness, delusions or hallucinations were present for a minimum of two weeks, without major mood symptoms.
- For a substantial part of the overall duration of both the active and residual period of the illness, symptoms meeting criteria for a mood episode are present.
- Symptoms are not caused by drug abuse, medication or another medical condition.