title: Psychological effects of implantable cardioverter defibrillator shocks. A review of study methods.
abstract: BACKGROUND
  The implantable cardioverter defibrillator (ICD) saves lives but clinical experience suggests that it may have detrimental effects on mental health. The ICD shock has been largely blamed as the main offender but empirical evidence is not consistent, perhaps because of methodological differences across studies.
  
  
  OBJECTIVE
  To appraise methodologies of studies that assessed the psychological effects of ICD shock and explore associations between methods and results.
  
  
  METHODS
  A comprehensive search of English articles that were published between 1980 and 30 June 2013 was applied to the following electronic databases: PubMed, EMBASE, NHS HTA database, PsycINFO, Sciencedirect and CINAHL.
  
  
  METHODS
  Only studies testing the effects of ICD shock on psychological and quality of life outcomes were included. Data were extracted according to a PICOS pre-defined sheet including methods and study quality indicators.
  
  
  RESULTS
  Fifty-four observational studies and six randomized controlled trials met the inclusion criteria. Multiple differences in methods that were used to test the psychological effects of ICD shock were found across them. No significant association with results was observed.
  
  
  CONCLUSIONS
  Methodological heterogeneity of study methods is too wide and limits any quantitative attempt to account for the mixed findings. Well-built and standardized research is urgently needed.
authors.affiliation: Psychology Research Laboratory, Istituto Auxologico Italiano IRCCS Verbania, Italy ; Department of Psychology, Catholic University of Milan Milano, Italy.
authors.forename: Gian Mauro
authors.initials: GM
authors.lastname: Manzoni
authors.affiliation: Psychology Research Laboratory, Istituto Auxologico Italiano IRCCS Verbania, Italy ; Department of Psychology, Catholic University of Milan Milano, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Castelnuovo
authors.affiliation: Department of Psychology, University of Bergamo Bergamo, Italy.
authors.forename: Angelo
authors.initials: A
authors.lastname: Compare
authors.affiliation: Department of Psychology, Catholic University of Milan Milano, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Pagnini
authors.affiliation: McGill University Health Center Montreal, QC, Canada.
authors.forename: Vidal
authors.initials: V
authors.lastname: Essebag
authors.affiliation: Cardiology Department, Luigi Sacco Hospital Milano, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Proietti
keywords: ICD shock; anxiety; depression; implantable cardioverter defibrillator; quality of life; review