Guest Editorial Diagnostic Concepts and the Prevention of Schizophrenia

chizophrenia has long been recognized as a devastating disorder for patients and their families. Although substan-tial progress has been achieved in both its diagnosis and treat-ment, and in understanding the disorder’s neurobiological substrates, a full understanding of its origins and pathogenic mechanisms remains elusive. One obstacle to better under-standing the causes of schizophrenia may be its diagnostic cri-teria (1). The DSM-IV and other nosologies provide a foundation for clinical diagnosis, but there is little basis for re-garding the DSM’s operational definition as the “true ” con-struct of schizophrenia. In the 1970s and 1980s, narrow diagnostic criteria for disor-ders like schizophrenia were needed to improve the reliability of clinical diagnoses. Research has also benefited from the re-liability of recent DSMs, in that clinical characteristics o