Minimal Important Change of the Scale for the Assessment and Rating of Ataxia (SARA) and the Modified Functional SARA (f-SARA) in Patient with Subacute Infratentorial Stroke: A Multicenter Prospective Observational Study.

This multicenter prospective longitudinal study aimed to estimate the minimal important change (MIC) for the Scale for the Assessment and Rating of Ataxia (SARA) and the modified functional SARA (f-SARA) in patients with subacute infratentorial stroke and ataxia undergoing rehabilitation. The study was conducted at inpatient rehabilitation units across five neurosurgical hospitals and included eighty patients with subacute infratentorial stroke. The SARA, f-SARA, and the Berg Balance Scale (BBS) were assessed at baseline (within three months of onset) and at follow-up (two and four weeks after baseline). Additionally, the Global Rating of Change (GRC) scale was used by both participants and therapists to assess subjective improvement in ataxia prior to the 2- and 4-week follow-ups. Patients were divided into two groups based on improvements in BBS (≥ 7 points) or GRC (≥ 5 points). MIC was calculated using a receiver operating characteristic-based method when the correlation between SARA/f-SARA change scores and the external anchors (BBS or GRC) was ≥ 0.3. The results showed that MICs for SARA and f-SARA could not be established using patient- or therapist-rated GRC. When the BBS served as the external anchor, the MIC for SARA was − 2.75 points at 2 weeks and − 4.75 points at 4 weeks. For f-SARA, the MIC was − 1.5 points at 2 weeks and − 2.5 to − 3.25 points at 4 weeks. In conclusion, the MIC values calculated in this study provide a useful benchmark for evaluating the effectiveness of interventions for ataxia and may guide clinical decision-making regarding intervention selection.