Assessment of structural and cross-cultural validity of the Disabilities of the Arm, Shoulder and Hand questionnaire: a scoping review

Introduction The Disabilities of the Arm, Shoulder and Hand (DASH) Questionnaire is a patient-reported outcome measure (PROM) that has been translated and cross-culturally adapted to at least 50 languages. Since the measure was developed in 1996, many researchers have reported on the construct validity (including structural and cross-cultural validity) of this instrument following translation and cross-cultural adaptation. The aim of this scoping review was to identify the methods used for the psychometric evaluation of structural and cross-cultural validity of the DASH questionnaire. Methods The updated methodological guidance for the conduct of scoping reviews and the PRISMA Extension for scoping reviews checklist was utilised. EBSCOHost (Academic Search Premier, Africa Wide, CINAHL, E-Journals and Medline), PubMed and Google Scholar were searched for articles (published between 1996-2022) and considered against the eligibility criteria. Results The scoping review collated evidence across 50 articles (37 language versions) of the evaluation of structural and cross-cultural validity of the DASH questionnaire. Three articles conducted confirmatory factor analysis (CFA) to assess structural validity, and none performed Multiple Group Confirmatory Factor Analysis (MGCFA) to assess cross-cultural validity. Conclusion The COnsensus-based Standards for the selection of health Measurement Instruments (COSMIN) taxonomy propose that structural validity is best evaluated through CFA, with prior evidence of dimensionality. Additionally, cross-cultural validity (measurement invariance) is to be evaluated through MGCFA. This review identified that CFA is utilised infrequently and that to date cross-cultural validity has not been appropriately assessed for translations of the DASH questionnaire.