Validation of the Spanish version of the cerebellar cognitive-affective syndrome scale

Objective: To validate the Spanish version of the Cerebellar Cognitive-Affective Syndrome scale (CCAS-S), originally published in 2018, in patients with cerebellar ataxia and healthy subjects, as an adapted Spanish version based on normative data has not yet been published or validated. Methods: Spanish CCAS-S was ­administered prospectively to 158 patients with cerebellar ataxia and 164 matched healthy subjects from ­different regions of Spain. Discriminant validity and reliability were evaluated. A subgroup of 30 patients underwent detailed neuropsychological examinations to confirm the construct validity. The Scale for the Assessment and Rating of Ataxia (SARA) and the Brief Ataxia Rating Scale (BARS) were used to assess motor performance. Results: This Spanish instrument demonstrates reliability and exhibits statistically significant differences in performance between patients and healthy subjects. Our analysis revealed lower values for specificity in detecting possible, probable, or definite CCAS compared to those reported in the US validation study when utilizing the original cutoff values. Upon application of the appropriate ­correction factor for education, the specificity values approximated those reported for probable and definite CCAS diagnostics in the original investigation. Conclusions: The adapted Spanish CCAS-S has demonstrated validity and good reliability in this cohort. Discriminant validity was satisfactory for probable and definite CCAS when the correction for education was applied, and modified template and instructions have been developed. Further research is necessary to investigate the significance of the possible CCAS category, as diagnosed using the Spanish version, as well as to assess the performance of the corrected scale in other Spanish-speaking countries.