Highlights
- •The minimally important change (MIC) for improvement of the 6-minute walking test is 19.7 m in patients with Multiple Sclerosis (MS).
- •The MIC for deterioration of the 6-minute walking test is 7.2 in the same patients.
- •The MICs can help physicians and therapist to evaluate their treatment.
Abstract
Background
The minimal important change (MIC) of the 6-minute walk test (6MWT) is not clear for
patients with Multiple Sclerosis (MS), hampering treatment evaluation. The aim of
our study was therefore to determine the MIC of the 6MWT in MS patients.
Methods
MS patients did the 6MWT using the instruction to walk at comfortable speed twice
with approximately one year in between. After the second 6MWT they completed 3-point
anchor question. The MICadjusted with a 95% confidence interval (CI) was calculated with the predictive modelling
method with bootstrapping.
Results
118 MS patients (mean age 48.2 years, 23.7% men) were included between September 2018
and October 2019. Mean 6MWT distance was 468 ± 112 m at baseline and 469 ± 115 m one
year later. Twenty-three (19.5%) patients answered their walking distance improved,
43 (36.4%) answered it worsened. A MICadjusted for improvement of 19.7 m (95%CI 9.8–30.9 m) was found, and for deterioration of
7.2 m (95%CI -3.3–18.2 m).
Conclusions
Using the most sophisticated statistical method, the MICadjusted of the 6MWT in MS patients was 19.7 m for improvement, and 7.2 m for deterioration.
This knowledge allows physiotherapists and physicians to evaluate if their treatment
has led to a meaningful improvement for their MS patients or if walking of their patients
has deteriorated.
Keywords
Abbreviations:
CI (confidence interval), COSMIN (COnsensus-based Standards for the selection of health Measurement Instruments), EDSS (Expanded Disability Status Scale), ICC (intraclass correlation coefficient), MIC (Minimal Important Change), MS (Multiple Sclerosis), 6MWT (6-Minute Walking Test), SD (standard deviation), ROC (receiver operating curve)To read this article in full you will need to make a payment
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Article info
Publication history
Published online: November 30, 2021
Accepted:
November 27,
2021
Received in revised form:
October 29,
2021
Received:
September 27,
2021
Identification
Copyright
© 2021 Elsevier B.V. All rights reserved.
