title: Translated Versions of Voice Handicap Index (VHI)-30 across Languages: A Systematic Review.
abstract: BACKGROUND
  In this systematic review, the aim is to investigate different VHI-30 versions between languages regarding their validity, reliability and their translation process.
  
  
  METHODS
  Articles were extracted systematically from some of the prime databases including Cochrane, googlescholar, MEDLINE (via PubMed gate), Sciencedirect, Web of science, and their reference lists by Voice Handicap Index keyword with only title limitation and time of publication (from 1997 to 2014). However the other limitations (e.g. excluding non-English, other versions of VHI ones, and so on) applied manually after studying the papers. In order to appraise the methodology of the papers, three authors did it by 12-item diagnostic test checklist in "Critical Appraisal Skills Programme" or (CASP) site. After applying all of the screenings, the papers that had the study eligibility criteria such as; translation, validity, and reliability processes, included in this review.
  
  
  RESULTS
  The remained non-repeated articles were 12 from different languages. All of them reported validity, reliability and translation method, which presented in details in this review.
  
  
  CONCLUSIONS
  Mainly the preferred method for translation in the gathered papers was "Brislin's classic back-translation model (1970), although the procedure was not performed completely but it was more prominent than other translation procedures. High test-retest reliability, internal consistency and moderate construct validity between different languages in regards to all 3 VHI-30 domains confirm the applicability of translated VHI-30 version across languages.
authors.affiliation: Dept. of Speech & Language Pathology, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Sadegh
authors.initials: S
authors.lastname: Seifpanahi
authors.affiliation: Biostatistics Division, School of Rehabilitation Sciences, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Shohreh
authors.initials: S
authors.lastname: Jalaie
authors.affiliation: School of Rehabilitation Sciences, Hamedan University of Medical Sciences, Hamedan, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Nikoo
authors.affiliation: Dept. of Speech Pathology, Paramedical Science Faculty, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Davood
authors.initials: D
authors.lastname: Sobhani-Rad
keywords: Reliability; Translation; VHI-30; Validity; Voice disorder; Voice handicap index