title: Validation of online psychometric instruments for common mental health disorders: a systematic review.
abstract: BACKGROUND
  Online questionnaires for measuring common mental health disorders such as depression and anxiety disorders are increasingly used. The psychometrics of several pen-and-paper questionnaires have been re-examined for online use and new online instruments have been developed and tested for validity as well. This study aims to review and synthesise the literature on this subject and provide a framework for future research.
  
  
  METHODS
  We searched Medline and PsycINFO for psychometric studies on online instruments for common mental health disorders and extracted the psychometric data. Studies were coded and assessed for quality by independent raters.
  
  
  RESULTS
  We included 56 studies on 62 online instruments. For common instruments such as the CES-D, MADRS-S and HADS there is mounting evidence for adequate psychometric properties. Further results are scattered over different instruments and different psychometric characteristics. Few studies included patient populations.
  
  
  CONCLUSIONS
  We found at least one online measure for each of the included mental health disorders and symptoms. A small number of online questionnaires have been studied thoroughly. This study provides an overview of online instruments to refer to when choosing an instrument for assessing common mental health disorders online, and can structure future psychometric research.
authors.affiliation: Department of Psychiatry, VU Medical Centre / GGZ inGeest, Amsterdam, Netherlands. w.van.ballegooijen@vu.nl.|Department of Clinical Psychology, Vrije Universiteit Amsterdam, Amsterdam, Netherlands. w.van.ballegooijen@vu.nl.|EMGO Institute for Health and Care Research, VU Medical Centre, Amsterdam, Netherlands. w.van.ballegooijen@vu.nl.
authors.forename: Wouter
authors.initials: W
authors.lastname: van Ballegooijen
authors.affiliation: Department of Clinical Psychology, Vrije Universiteit Amsterdam, Amsterdam, Netherlands. h.riper@vu.nl.|EMGO Institute for Health and Care Research, VU Medical Centre, Amsterdam, Netherlands. h.riper@vu.nl.
authors.forename: Heleen
authors.initials: H
authors.lastname: Riper
authors.affiliation: Department of Clinical Psychology, Vrije Universiteit Amsterdam, Amsterdam, Netherlands. p.cuijpers@vu.nl.|EMGO Institute for Health and Care Research, VU Medical Centre, Amsterdam, Netherlands. p.cuijpers@vu.nl.
authors.forename: Pim
authors.initials: P
authors.lastname: Cuijpers
authors.affiliation: Department of Psychiatry, VU Medical Centre / GGZ inGeest, Amsterdam, Netherlands. p.vanoppen@ggzingeest.nl.|EMGO Institute for Health and Care Research, VU Medical Centre, Amsterdam, Netherlands. p.vanoppen@ggzingeest.nl.
authors.forename: Patricia
authors.initials: P
authors.lastname: van Oppen
authors.affiliation: Department of Psychiatry, VU Medical Centre / GGZ inGeest, Amsterdam, Netherlands. jh.smit@ggzingeest.nl.|EMGO Institute for Health and Care Research, VU Medical Centre, Amsterdam, Netherlands. jh.smit@ggzingeest.nl.
authors.forename: Johannes H
authors.initials: JH
authors.lastname: Smit
mesh_terms: D001008:Anxiety Disorders / Q000175:diagnosis; D003863:Depression / Q000175:diagnosis; D003866:Depressive Disorder / Q000175:diagnosis; D003936:Diagnosis, Computer-Assisted / Q000379:methods / Q000592:standards*; D006801:Humans; D020407:Internet / Q000706:statistics & numerical data*; D001523:Mental Disorders / Q000175:diagnosis*; D008603:Mental Health; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics / Q000379:methods; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*