Which disorder requires the presence of psychosis for diagnosis?

Schizophrenia is a psychiatric disorder characterized specifically by the presence of psychotic symptoms. These symptoms can include delusions, hallucinations, disorganized thinking, and impaired functioning. For a diagnosis of schizophrenia, the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) notes that at least one of the symptoms must be a core psychotic feature, such as delusions or hallucinations. This distinguishes schizophrenia from other mood and anxiety disorders, where psychosis is not a requisite for the diagnosis.

In contrast, while major depressive disorder and bipolar disorder can involve psychotic features, these features are not necessary for their diagnosis. In major depressive disorder, the presence of psychotic features may indicate a more severe form of depression but is not required. Similarly, in bipolar disorder, psychotic symptoms can occur during manic or depressive episodes but are not essential for the diagnosis. Generalized anxiety disorder does not involve psychosis at all, instead focusing on excessive worry and anxiety without the reality-distorting symptoms seen in psychosis. Thus, only schizophrenia is specifically defined by the necessity of psychotic symptoms for its diagnosis.