BackgroundThe Mini-BESTest is a clinical balance test that has shown a high sensitivity in detecting balance impairments in elderly with Parkinson's disease (PD). However, its reproducibility between different raters and between test occasions has yet to be investigated in a clinical context. Moreover, no one has investigated the reproducibility of the Mini-BESTest's subcomponents (i.e. anticipatory postural adjustments; postural responses; sensory orientation and dynamic gait).We aimed to investigate the inter-rater and test-retest reproducibility (reliability as well as agreement) of the Mini-BESTest, as well as its subcomponents, in elderly with mild to moderate PD, performed under conditions assimilating clinical practice.MethodThis was an observational measurement study with a test-retest design.Twenty-seven individuals with idiopathic PD (66 - 80 years, mean age: 73; Hoehn & Yahr: 2-3; 1-15 years since diagnosis) were included. Two test administrators, having different experiences with the Mini-BESTest, administered the test individually, in separate rooms in a hospital setting. For the test-retest assessment, all participants returned 7 days after the first test session to perform the Mini-BESTest under similar conditions. Intra-class correlation coefficients (ICC2.1), standard error of measurement (SEMagreement), and smallest real difference (SRD) were analyzed.ResultsThe Mini-BESTest showed good reliability for both inter-rater and test-retest reproducibility (ICC = 0.72 and 0.80). Regarding agreement, the measurement error (SRD) was found to be 4.1 points (accounting for 15% of the maximal total score) for inter-rater reproducibility and 3.4 points (12% of the maximal total score) for test-retest reproducibility. The investigation of the Mini-BESTest's subcomponents showed a similar pattern for both inter-rater and test-retest reproducibility, where postural responses had the largest proportional measurement error, and sensory orientation showed the highest agreement.ConclusionsOur findings indicate that the Mini-BESTest is able to distinguish between individuals with mild to moderate PD; however, when used in clinical balance assessments, the large measurement error needs to be accounted for.

Recently, a comprehensive clinical balance test, the balance evaluation systems test (BESTest), was developed to identify the postural control systems causing balance impairments. A short version, the mini-BESTest, was thereafter developed by eliminating redundant and insensitive items. This study aimed to translate the mini-BESTest to Swedish, adapt it and investigate its validity in subjects with Parkinson's disease (PD) or stroke. The Mini-BESTest was translated and back-translated in accordance with Guillemin's guidelines. Discrepancies were discussed and solved by a panel and the test was culturally adapted. Concurrent validity of the final version was explored by correlating well-known clinical tests - the Berg Balance Scale (BBS), the Timed Up and Go (TUG) test and the Falls Efficacy Scale (FES(s)) - with the new mini-BESTest in nine subjects with mild-to-moderate PD (60 years, range 46-85) and nine with chronic stroke (78 years, range 66-90). A high-to-very-high correlation was shown between the mini-BESTest and the BBS (PD: r(s) =0.94, stroke: r(s) =0.86). The mini-BESTest correlated highly with the TUG (PD: r(s) = -0.81, stroke: r(s) = -0.89). In the PD group, a low correlation (r(s) =0.26) was seen between the mini-BESTest and the FES(s). The mini-BESTest has high concurrent validity and is a comprehensive assessment of balance. However, its psychometric properties should be evaluated further.