Minimal clinically important difference of the Kansas University standing balance scale in patients with acute-to-subacute stroke using two external anchors

Stroke-related balance impairments reduce independence, making accurate assessment vital for rehabilitation. However, research on the minimal clinically important difference for the Kansas University Standing Balance Scale (KUSBS) is limited. This study determined the minimal clinically important difference for the KUSBS based on reduced assistance in walking and daily living activities for inpatients with acute-to-subacute stroke. This retrospective study included 407 inpatients diagnosed with acute-to-subacute stroke who were referred to the rehabilitation department between 2016 and 2022. Clinical outcomes – including the Kansas University Standing Balance Scale (KUSBS), Berg Balance Scale (BBS), Functional Ambulation Category (FAC), and Modified Barthel Index (MBI) – were assessed at both admission and discharge. The minimal clinically important difference was determined using anchor-based methods, including receiver operating characteristic curve analysis. The minimal clinically important difference for the KUSBS was 0.5 for both anchors; for the BBS, it ranged from 5.5 to 9.5. Subgroup analysis demonstrated statistical significance for patients requiring assistance with activities. Multivariate analysis indicated that functional improvements varied according to the initial functional levels. The minimal clinically important difference for the KUSBS was 0.5 for patients requiring walking assistance and 1.5 for those needing maximal assistance with daily activities. Alternative balance assessment tools may be more suitable for patients who do not require assistance. Our study findings emphasize the importance of incorporating qualitative balance assessment tools, such as the KUSBS, alongside traditional quantitative measures, such as the BBS, to provide a more comprehensive evaluation of post-stroke balance function.