title: Equivalence of electronic and paper-based patient-reported outcome measures.
abstract: OBJECTIVE
  Electronic formats (ePROs) of paper-based patient-reported outcomes (PROs) should be validated before they can be reliably used. This review aimed to examine studies investigating measurement equivalence between ePROs and their paper originals to identify methodologies used and to determine the extent of such validation.
  
  
  METHODS
  Three databases (OvidSP, Web of Science and PubMed) were searched using a set of keywords. Results were examined for compliance with inclusion criteria. Articles or abstracts that directly compared screen-based electronic versions of PROs with their validated paper-based originals, with regard to their measurement equivalence, were included. Publications were excluded if the only instruments reported were stand-alone visual analogue scales or interactive voice response formats. Papers published before 2007 were excluded, as a previous meta-analysis examined papers published before this time.
  
  
  RESULTS
  Fifty-five studies investigating 79 instruments met the inclusion criteria. 53 % of the 79 instruments studied were condition specific. Several instruments, such as the SF-36, were reported in more than one publication. The most frequently reported formats for ePROs were Web-based versions. In 78 % of the publications, there was evidence of equivalence or comparability between the two formats as judged by study authors. Of the 30 publications that provided preference data, 87 % found that overall participants preferred the electronic format.
  
  
  CONCLUSIONS
  When examining equivalence between paper and electronic versions of PROs, formats are usually judged by authors to be equivalent. Participants prefer electronic formats. This literature review gives encouragement to the further widespread development and use of ePROs.
authors.affiliation: Centre for Socioeconomic Research, School of Pharmacy and Pharmaceutical Sciences, Cardiff, UK.
authors.forename: Niloufar
authors.initials: N
authors.lastname: Campbell
authors.forename: Faraz
authors.initials: F
authors.lastname: Ali
authors.forename: Andrew Y
authors.initials: AY
authors.lastname: Finlay
authors.forename: Sam S
authors.initials: SS
authors.lastname: Salek
mesh_terms: D003199:Computer Systems; D006801:Humans; D010147:Pain Measurement / Q000379:methods*; D010209:Paper; D063868:Patient Outcome Assessment; D011788:Quality of Life; D057566:Self Report; D012986:Software Validation