What is the chief difference between schizophrenia and schizoaffective disorder?

• A. presence of major depression or mania concurrent with schizophrenia symptoms in schizoaffective disorder
• B. age of onset
• C. severity of negative symptoms
• D. presence of catatonia

Answer: (A)

The main idea is that schizoaffective disorder blends psychotic symptoms with a major mood disorder, while schizophrenia does not require concurrent mood episodes. In schizoaffective disorder, you have the core psychotic features (delusions, hallucinations, disorganized thinking) plus a major depressive or manic episode that occurs at the same time as those psychotic symptoms. Importantly, there must also be a period when psychotic symptoms are present without any major mood episode, showing that psychosis isn’t solely tied to mood. That combination—psychotic symptoms with mood episodes, plus a distinct period of psychosis without mood symptoms—is what sets schizoaffective disorder apart from schizophrenia or from mood disorders with psychotic features. The other aspects listed (age of onset, how severe negative symptoms are, or the presence of catatonia) can occur in either condition and don’t define the difference.