Responsiveness and Minimal Clinically Important Difference of Balance Assessment Tools in Parkinson's Disease.

BACKGROUND

Responsiveness and minimal clinically important difference (MCID) are among the psychometric properties necessary for interpreting results. However, responsiveness and MCID of the Falls Efficacy Scale-International (FES-I) and the Biodex Balance System (Biodex-BS) in individuals with Parkinson's disease (PD) have not yet been determined.

OBJECTIVES

The objective of this study is to establish the responsiveness and MCID of FES-I and Biodex-BS, as well as Berg Balance Scale, Time up and Go (TUG) test, Tinetti Gait and Balance Scale (TGBS), and Mini-Balance Evaluation Systems Test in PD.

METHODS

In this prospective observational cohort study, 86 individuals with PD were assessed. Responsiveness was evaluated utilizing 11 predefined hypotheses. MCID was calculated using anchor and distribution-based methods. In this study, the Global Rating of Change-Patient (GRC-P) and Global Rating of Change-Therapist (GRC-T) and the Activity-Specific Balance Confidence Scale (ABC) were used as anchors. ROC analysis was utilized in the anchor-based method.

RESULTS

The Fall Risk Test-Overall Stability Index (FRT-OSI), one of the Biodex-BS parameters, showed the highest responsiveness. TUG and FES-I indicated a substantial responsiveness, while the TGBS demonstrated the lowest responsiveness. MCID of FRT-OSI, which had the highest responsiveness, had 0.78 with the distribution-based method. In the anchor-based method, MCID with GRC-P, GRC-T, and ABC anchors were 0.54, 0.95, and 0.54, respectively.

CONCLUSIONS

FRT-OSI demonstrated the highest responsiveness in PD. TUG and FES-I may be used as alternatives when a Biodex-BS is inaccessible. TGBS clinical utility may be limited. MCIDs determined in this study may help interpret the clinical importance of the results.