Abstract
Deconstructing Schizophrenia for DSM-V: Challenges for Clinical and Research Agendas
Author(s): Joseph M. PierreConsiderable effort is focused on a revised definition of schizophrenia for the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM) anticipated in 2012. Among the core debates are how to define a disorder without an established pathophysiology, whether diagnosis is improved by implementing continuous symptomatic dimensions, and to what extent neurocognitive deficits should be integrated into schizophrenia for DSM-V. Although lacking in validity, the diagnosis “schizophrenia” remains a useful term for clinical communication, with current antipsychotic therapies encouraging diagnostic “lumping” rather than “splitting.” Much evidence supports a move to a dimensional model for psychosis, but doing so raises the potential for overdiagnosis. Validity problems exist not only with schizophrenia, but also with its defining symptoms such as delusions and hallucinations. Integrating dimensional symptom clusters into DSM-V schizophrenia, exemplified by models based on neurocognitive deficits, offers a strategic shift of focus onto core symptoms both within, and across, categorical diagnoses. Such a shift is consistent with existing clinical practice, and could pave the way toward more meaningful and scientifically validated reformulations of diagnostic categories in further revisions of DSM