Age-related reference values for the pediatric Scale for Assessment and Rating of Ataxia: a multicentre study

AimFor reliable assessment of ataxia severity in children, the Childhood Ataxia and Cerebellar Group of the European Pediatric Neurology Society aimed to validate the Scale for Assessment and Rating of Ataxia (SARA) according to age. MethodTwenty-two pediatric ataxia experts from 15 international institutions scored videotaped SARA performances in 156 typically developing children (4-16y: m/f=1; 12 children per year of age; including nine different nationalities). We determined age-dependency and reliability of pediatric SARA scores by a mixed model. ResultsIn typically developing children, age was the only variable that revealed a relationship with SARA scores (p<0.001). The youngest children revealed the highest scores and the highest variation in scores (<8y; p<0.001). After 11 years of age, pediatric scores approached adult outcomes. The interobserver agreement of total SARA scores was substantial with an intraclass correlation coefficient of 0.63 (95% confidence interval 0.56-0.69; p<0.001). InterpretationIn typically developing European children, both SARA scores and interobserver agreement are age-dependent. For reliable interpretation of pediatric SARA scores, consideration of the underlying test construct appears prudent. These data will hopefully contribute to a correct and uniform interpretation of longitudinal SARA scores from childhood to adulthood.