title: Improving classification of psychoses.
abstract: Psychosis has been recognised as an abnormal state in need of care throughout history and by diverse cultures. Present classifications of psychotic disorder remain based on the presence of specific psychotic symptoms, relative to affective and other symptoms, and their sequence and duration. Although extant diagnostic classifications have restricted validity, they have proven reliability and most clinicians and some patients find them useful. Moreover, these classifications have yet to be replaced by anything better. We propose that an expansion of the subgrouping approach inherent to classification will provide incremental improvement to present diagnostic constructs-as has worked in the rest of medicine. We also propose that subgroups could be created both within and across present diagnostic classifications, taking into consideration the potential value of continuous measures (eg, duration of psychotic symptoms and intelligence quotient). Health-care workers also need to work with service users and carers to develop and adapt approaches to diagnosis that are seen as helpful.
authors.affiliation: Department of Psychiatry, Kennedy Tower, Royal Edinburgh Hospital, Edinburgh, UK. Electronic address: s.lawrie@ed.ac.uk.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Lawrie
authors.affiliation: MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, UK.
authors.forename: Michael C
authors.initials: MC
authors.lastname: O'Donovan
authors.affiliation: USC Gould School of Law, University of Southern California, Los Angela, CA, USA.
authors.forename: Elyn
authors.initials: E
authors.lastname: Saks
authors.affiliation: Department of Psychiatry, University of Oxford, Oxford, UK.
authors.forename: Tom
authors.initials: T
authors.lastname: Burns
authors.affiliation: Columbia University College of Physicians and Surgeons, New York State Psychiatric Institute, New York, NY, USA.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Lieberman
mesh_terms: D006801:Humans; D011618:Psychotic Disorders / Q000145:classification* / Q000175:diagnosis; D016032:Randomized Controlled Trials as Topic; D015203:Reproducibility of Results