For a diagnosis of schizophrenia, how long must active symptoms be present according to criterion A?

• A. One week
• B. Two weeks
• C. Three months
• D. One month

Answer: (D)

Active symptoms must be present for at least one month. During a one-month period, the person must experience a significant portion of time with at least two of the following symptoms, and at least one of those must be delusions, hallucinations, or disorganized speech. This one-month timeframe defines the active phase used in criterion A. If symptoms last less than a month, schizophrenia isn’t met by criterion A alone; if the total illness duration falls between one and six months, a different diagnosis like schizophreniform disorder may be considered, while the overall course of schizophrenia requires broader duration (typically at least six months including prodromal or residual periods).