Linguistic Validation and Cross-Cultural Adaptation of the Canine Orthopedic Index for the German- and Spanish-speaking Population.

The Canine Orthopedic Index (COI) questionnaire was developed to assess chronic pain and functional impairment in dogs with orthopaedic conditions. This study aimed to perform a linguistic validation and cross-cultural adaptation of the COI from the original English version into Universal German and Universal Spanish.We employed the Functional Assessment of Chronic Illness Therapy translation methodology, which involves two forward translations, one reconciliation of the two forward translations, a back translation into English, multiple reviews, and cognitive debriefing interviews with a representative sample of dog carers. We followed a universal approach to translation, with translators and study participants from different German- and Spanish-speaking countries.The two independent forward translations differed by four parts for the German COI and eight parts for the Spanish COI. Comparing the backward translations with the original document identified 10 items or instructions in both translations that required retranslation. Cognitive debriefing interviews with dog carers confirmed that the translated instruments effectively conveyed the same concepts as the original version, leading to no further changes in the Universal German COI and four minor revisions to the Universal Spanish COI.We provide linguistically validated and culturally adapted versions of the COI suitable for use in all German- and Spanish-speaking countries.