OTHER DISORDERS CAN easily be mistaken for schizophrenia if a patient's symptoms are not examined closely. It is not clear how these other psychotic disorders are related to schizophrenia. They do have features in common, but they also show significant differences. It might be useful to think of schizophrenia as a spectrum of diseases that blend into each other. The spectrum might include the subtypes of schizophrenia, delusional disorders, schizoaffective disorders, and other diseases that show a close association with schizophrenia through common traits and inheritance patterns.