Schizoaffective disorder (SZA, SZD or SAD) is a mental disorder characterized by abnormal thought processes and an unstable mood. The diagnosis is made when the person has symptoms of both schizophrenia (usually psychosis) and a mood disorder—either bipolar disorder or depression. The main criterion for the schizoaffective disorder diagnosis is the presence of psychotic symptoms for at least two weeks without any mood symptoms present. Schizoaffective disorder can often be misdiagnosed when the correct diagnosis may be psychotic depression, psychotic bipolar disorder, schizophreniform disorder, or schizophrenia. It is imperative for providers to accurately diagnose patients, as treatment and prognosis differs greatly for each of these diagnoses.