Cross-cultural Adaptation and Translation Validation of the iADH Universal Case Mix Tool (UCMT).

This study is a multicentre, non-interventional methodological study aimed at translating, culturally adapting, and validating the iADH Universal case mix tool (UCMT) for use by dental care professionals working with people living with disabilities, following international guidelines for cross-cultural adaptation of measurement instruments. The translation and cultural adaptation process will include forward and backward translations of the original UCMT (English) to German, Spanish and Portuguese. Two independent forward translations will be performed for each language, followed by reconciliation into a single version, based on semantic equivalence, clarity and cultural appropriateness. Blinded backward translations into English will then be conducted to ensure conceptual consistency with the original instrument. A panel of experts, composed of dental experts and linguistic professionals fluent in both languages will review all translated versions using a Delphi approach. Later, the adapted instruments will be reviewed by the original UCMT developers for the final approval. Consent Validity Index (CVI) of the translated UCMT will be evaluated through expert ratings and cognitive interviews with dental professionals experienced in special care dentistry. Following the experts' validation, a pilot reliability phase will be conducted using standardised online clinical cases developed for the original versions of the UCMT. Participating raters will complete an online questionnaire using the translated UCMT. Intra and interrater agreement will be assessed to evaluate consistency of the translated instrument in a simulated clinical scenario. This study does not involve real patients of the collection of sensitive personal data.

• Interrater agreement of the UCMT domains scores [Time frame: 1 month]
• Temporal stability (Test-retest) of UCMT domain scores [Time frame: 2 weeks]