[ABSTRACT] Late onset schizophrenia is a controversial medical diagnosis. Although schizophrenia is generally regarded as an illness with onset in late adolescence or early adult life, a sizeable minority of patients first become ill in middle or old age. However, inconsistencies in diagnostic systems and nomenclature, coupled with a tendency among most schizophrenia researchers to ascribe late-onset psychoses to organic factors, have led to such cases occupying an ambiguous position in relation