Minimal clinically important difference of the Brief-BESTest in COPD

Abstract

Balance training within pulmonary rehabilitation (PR) improves balance of people with COPD. Brief-Balance Evaluation System Test (Brief-BESTest) is a balance test commonly used to assess balance; however, the clinical interpretability of its improvements is impaired by the lack of established minimal clinically important differences (MCIDs). This study established the MCID of the Brief-BESTest in people with COPD. The MCID was computed using anchor (mean changes, linear regressions) and distribution (0.5*SD, standard error of measurement - SEM, 1.96*SEM and minimal detectable change) based methods. Changes in the 6-minute walk test (6MWT) and the modified Medical Research Council dyspnoea scale (mMRC) were assessed pre/post a 12-week PR programme, with exercise/balance training 2x/week, and used as anchors. Pooled MCIDs were computed using the arithmetic weighted mean (2/3 for anchor- and 1/3 for distribution-based methods). 68 people with COPD (69±8 yrs; 51 male; FEV1 49±17pp) completed the PR programme. Significant correlations were found between the Brief-BESTest and the 6MWT (r=0.34; p=0.005), and the mMRC (r=-0.33; p=0.007). The pooled MCID was 3.3 points (Fig. 1). An improvement ≥3 points in the Brief-BESTest seems to be clinically meaningful in people with COPD following PR with balance training. The estimated MCID will aid health professionals to interpret the effects of PR on balance performance and guide tailored interventions.