There are no medical tests to diagnose schizophrenia. A psychiatrist should examine the patient to make the diagnosis. The diagnosis is made based on a thorough interview of the person and family members. The doctor will ask questions about:

• How long the symptoms have lasted
• How the person's ability to function has changed
• Developmental background
• Genetic and family history
• How well medications have worked

Brain scans (such as CT or MRI) and blood tests may help to rule out other disorders that have similar symptoms to schizophrenia.