Which disorder meets the schizophrenia criteria but has symptoms present for less than 6 months?

Schizophreniform disorder is characterized by the presence of symptoms that meet the criteria for schizophrenia but occur for a duration of at least one month and less than six months. This disorder allows for a diagnosis when a patient exhibits typical psychotic symptoms such as delusions, hallucinations, disorganized speech, and negative symptoms, which are similar to those seen in schizophrenia, but the shorter duration distinguishes it from a full schizophrenia diagnosis.

The criteria for schizophrenia require symptoms to be present for at least six months, which is why schizophrenia itself would not fit. Schizoaffective disorder involves both mood symptoms and psychotic symptoms and is not limited by the duration of psychotic symptoms alone. Delusional disorder primarily focuses on the presence of non-bizarre delusions without the full-blown symptoms of schizophrenia, making it a different category altogether. Thus, the specific timeframe of symptoms is pivotal, and schizoaffective disorder is the only option that fits the requirement of having symptoms present for under six months while still meeting the broader criteria of schizophrenia-related disorders.