The Italian Standardization of the Cerebellar Cognitive Affective/Schmahmann Syndrome Scale: Cognitive Profiling in a Healthy, Heterogeneous Population.

Introduction: The Cerebellar Cognitive Affective Syndrome (CCAS), also known as Schmahmann's syndrome, is increasingly recognized for its impact on cognitive and emotional functioning yet remains underdiagnosed. This study aimed to standardize the CCAS-Scale (CCAS-S) in the Italian population, enhancing its methodological and statistical validity.

Methods: A total of 671 healthy Italian volunteers (mean age = 46.19 years with SD 18.47, 58.88% females), were recruited from various geographical, educational and social backgrounds. Participants were assessed using the CCAS-S, alongside the Cognitive Reserve Index questionnaire, Raven's Colored Progressive Matrices and the Mini-Mental State Examination to ensure a comprehensive assessment and establish convergent validity. Moreover, the parallel CCAS-S version B was administered to 51 individuals.

Results: Statistical analyses on the Italian version of the CCAS-S revealed strong psychometric properties. Internal consistency was confirmed with Cronbach's alpha values of 0.70 and 0.74 for parallel forms A and B. Construct validity was supported by a moderate-to-high correlation (r = 0.453) with the Mini-Mental State Examination, suggesting both scales are related yet measure different cognitive functions, with the CCAS-S focusing on executive functions. Test-retest and inter-rater reliability were optimal (ICC = 0.902 and 0.989, respectively). Minimal practice effects were observed after 1 to 3 months, with further validation achieved using parallel version B.

Conclusions: The present work provides the first Italian standardization of CCAS-S. The results highlight the necessity for increased awareness and recognition of CCAS in clinical settings, advocating for the integration of the CCAS-S into routine assessments to improve diagnostic accuracy and patient care.