Cross-cultural adaptation and validation of the Diabetic Foot Questionnaire (DiaFootQ) into Spanish Language

To perform a cross-cultural adaptation and validation of the Diabetic Foot Questionnaire (DiaFootQ) into Spanish (DiaFootQ-Sp).

Cross-cultural adaptation, validity and reliability study. SITE: Diabetic Foot Unit (Regional University Hospital of Malaga, Spain), Podiatry Teaching Unit (University of Malaga, Spain) and private clinics across Spain.

Adults over 18 years old with type 2 diabetes mellitus who were referred for diabetic foot examination or already enrolled with DFD.

An observational study was conducted in two phases: (1) translation and cross-cultural adaptation of the DiaFootQ into Spanish and (2) psychometric validation of the DiaFootQ-Sp. Recommendations by ISPOR Task Force for Translation and Cultural Adaptation were followed. Reliability and validity were assessed using internal consistency (Cronbach's α), test-retest reliability (ICC), and construct validity through factor analysis. Criterion validity was evaluated by correlating DiaFootQ-Sp with the Foot Function Index (FFI), SF-12v2, and EuroQoL.

A total of n=466 participants completed the study. The DiaFootQ-Sp showed strong internal consistency (Cronbach's α=0.903) and high test-retest reliability (ICC=0.854-0.997). Sensitivity analysis reported SEM=2.195 and MDC90=5.121. Construct validity was confirmed (KMO=0.677, Bartlett's test p<0.001). Criterion validity showed significant correlations with the EuroQol-5D (r=0.889) and SF-12 (r=0.353). The mean completion time was 8.61min.

DiaFootQ was successfully adapted and validated for Spanish-speaking population, providing a useful and reliable tool to assess patients with DFD. The quality of care and prevention might be enhanced by implementing this instrument in clinical practice.