title: Subscales of the vestibular activities and participation questionnaire could be applied across cultures.
abstract: OBJECTIVE
  The objective of this study was to assess the objectivity, cross-cultural validity, and convergent validity of the Vestibular Activities and Participation (VAP) questionnaire among four countries, Germany, United States, Jordan, and Saudi Arabia.
  
  
  METHODS
  This was a cross-sectional study conducted in four specialized outpatient dizziness clinics in Germany, United States, Jordan, and Saudi Arabia.
  
  
  RESULTS
  A total of 453 participants were included in the study. The Rasch analysis revealed two separate subscales. Subscale 1 items included focusing attention, lying down, standing, bending, lifting and carrying objects, and sports. Subscale 2 items included walking long distances, climbing, running, moving around within buildings other than home, using transportation, and driving. The Pearson product-moment correlation between the Dizziness Handicap Inventory and the summary score of the VAP subscale 1 was 0.66 and was 0.64 for subscale 2.
  
  
  CONCLUSIONS
  Owing to its shortness and intercultural adaptability, the new two-scale version of the VAP questionnaire lends itself to clinical practice and research across countries to estimate the effect of vertigo and dizziness on activity limitation and participation restrictions. Psychometrically sound summary scores can be calculated. More extended versions of the VAP can be used for comprehensive clinical assessment where summary scores are not needed or a more detailed documentation is warranted.
authors.affiliation: Institute for Medical Information Processing, Biometrics and Epidemiology, Ludwig-Maximilians-Universität München, Marchioninistr. 17, D-81377 Munich, Germany; German Center for Vertigo and Balance Disorders, Ludwig-Maximilians-Universität München, Marchioninistr. 17, D-81377 Munich, Germany. Electronic address: martin.mueller@med.uni-muenchen.de.
authors.forename: Martin
authors.initials: M
authors.lastname: Mueller
authors.affiliation: Department of Physical Therapy, University of Pittsburgh, Bridgeside Point 1 100 Technology Drive, Pittsburgh, PA 15219-3130, USA; Department of Otolaryngology, University of Pittsburgh, 203 Lothrop Street, Pittsburgh, PA 15213, USA; Department of Rehabilitation Sciences, King Saud University, Riyadh 11433, Saudi Arabia.
authors.forename: Susan L
authors.initials: SL
authors.lastname: Whitney
authors.affiliation: Department of Physical Therapy, The University of Jordan, Queen Rania Street, Amman-11942, Jordan.
authors.forename: Alia
authors.initials: A
authors.lastname: Alghwiri
authors.affiliation: Department of Physical Therapy, University of Pittsburgh, Bridgeside Point 1 100 Technology Drive, Pittsburgh, PA 15219-3130, USA.
authors.forename: Kefah
authors.initials: K
authors.lastname: Alshebber
authors.affiliation: Institute for Medical Information Processing, Biometrics and Epidemiology, Ludwig-Maximilians-Universität München, Marchioninistr. 17, D-81377 Munich, Germany; German Center for Vertigo and Balance Disorders, Ludwig-Maximilians-Universität München, Marchioninistr. 17, D-81377 Munich, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Strobl
authors.affiliation: Department of Rehabilitation Sciences, College of Applied Medical Sciences, King Saud University, Riyadh 11433, Saudi Arabia; Rehabilitation Research Chair, Department of Rehabilitation Sciences, College of Applied Medical Sciences, King Saud University, Riyadh 11433, Saudi Arabia.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Alghadir
authors.affiliation: ENT Department, College of Medicine, King Saud University, Riyadh 12372-4392, Saudi Arabia.
authors.forename: Murad O
authors.initials: MO
authors.lastname: Al-momani
authors.affiliation: Department of Otolaryngology, University of Pittsburgh, 203 Lothrop Street, Pittsburgh, PA 15213, USA.
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Furman
authors.affiliation: Institute for Medical Information Processing, Biometrics and Epidemiology, Ludwig-Maximilians-Universität München, Marchioninistr. 17, D-81377 Munich, Germany; German Center for Vertigo and Balance Disorders, Ludwig-Maximilians-Universität München, Marchioninistr. 17, D-81377 Munich, Germany.
authors.forename: Eva
authors.initials: E
authors.lastname: Grill
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D003431:Cross-Cultural Comparison; D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D004244:Dizziness / Q000175:diagnosis / Q000523:psychology / Q000534:rehabilitation*; D005260:Female; D005858:Germany; D006801:Humans; D007597:Jordan; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D010358:Patient Participation; D011594:Psychometrics; D015203:Reproducibility of Results; D012529:Saudi Arabia; D011795:Surveys and Questionnaires; D014481:United States; D014717:Vertigo / Q000175:diagnosis / Q000523:psychology / Q000534:rehabilitation*
keywords: Activities of daily living; Dizziness; ICF; Quality of life; Social participation; Vertigo