title: The obsessive compulsive spectrum in schizophrenia, a meta-analysis and meta-regression exploring prevalence rates.
abstract: OBJECTIVE
  The aims of this study were to conduct a meta-analysis and meta-regression to estimate the prevalence rates for obsessive compulsive symptoms (OCS) and obsessive compulsive disorder (OCD) in schizophrenia, and to investigate what influences these prevalence rates.
  
  
  METHODS
  Studies were identified via an online OVID database search, including PsychInfo, Embase and Medline until December 2009.
  
  
  RESULTS
  Forty-three studies summarizing outcomes for 3978 subjects met inclusion criteria. The mean OCD prevalence is 12.3%, slightly increasing to 13.6% after adjustment in meta-regression. The prevalence rate of OCS, defined as any obsession or compulsion is 30.7% (30.3% adjusted). Higher severity of OCS, DIGS assessment, and Sub-Saharan African origin of study are associated with a lower OCS/OCD prevalence rate, use of DSM-IV edition, Y-BOCS assessment and longer schizophrenia history are associated with a higher prevalence rate.
  
  
  CONCLUSIONS
  The prevalence of OCS and OCD in schizophrenia is substantial, specifically in more chronic patient populations and is influenced by the method of assessment.
authors.affiliation: Arkin Mental Health and Addiction Treatment Centre, Amsterdam, The Netherlands. Electronic address: marijeswets@upcmail.nl.
authors.forename: Marije
authors.initials: M
authors.lastname: Swets
authors.affiliation: Arkin Mental Health and Addiction Treatment Centre, Amsterdam, The Netherlands; Department of Clinical Psychology, VU Amsterdam, The Netherlands.
authors.forename: Jack
authors.initials: J
authors.lastname: Dekker
authors.affiliation: Arkin Mental Health and Addiction Treatment Centre, Amsterdam, The Netherlands; Department of Psychiatry, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands; Amsterdam Institute for Addiction Research, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Katelijne
authors.initials: K
authors.lastname: van Emmerik-van Oortmerssen
authors.affiliation: Foundation Centrum'45/Arq, Diemen, The Netherlands.
authors.forename: Geert E
authors.initials: GE
authors.lastname: Smid
authors.affiliation: Trimbos-instituut, Netherlands Institute of Mental Health and Addiction, Utrecht, The Netherlands; Department of Epidemiology and Biostatistics, EMGO Institute for Health and Health Care Research, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Filip
authors.initials: F
authors.lastname: Smit
authors.affiliation: AMC, Department of Psychiatry, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Lieuwe
authors.initials: L
authors.lastname: de Haan
authors.affiliation: Arkin Mental Health and Addiction Treatment Centre, Amsterdam, The Netherlands; Department of Psychiatry, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Schoevers
mesh_terms: D016206:Databases, Bibliographic / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D009771:Obsessive-Compulsive Disorder / Q000145:classification / Q000150:complications / Q000453:epidemiology*; D015995:Prevalence; D011569:Psychiatric Status Rating Scales; D012044:Regression Analysis; D012559:Schizophrenia / Q000150:complications / Q000453:epidemiology*
keywords: Meta-analysis; Obsessive compulsive disorder; Psychotic disorder; Schizophrenia