The clinical heterogeneity of schizophrenia has seriously hindered the progress of knowledge concerning the etiopathogenesis of the syndrome and the development of more specific treatments. Several approaches have been proposed to identify clinically homogeneous subtypes based on the predominance of positive or negative symptoms in the clinical picture. However, these approaches suffer from several limitations, including subtype variability over time and heterogeneity within the positive and negative domains . The concept of “Deficit Schizophrenia” (DS) was introduced to identify a relatively homogeneous subgroup of patients with the diagnosis of schizophrenia, characterized by the presence of enduring, primary negative symptoms. The diagnosis of DS is based on operational criteria provided in the “Schedule for the Deficit Syndrome”, a semistructured interview that our group translated into Italian. This translation is presented here.
