Validation of questionnaire for patients with myotonia – Czech version of Myotonia Behaviour Scale

Czech version

Authors: M. Horáková; T. Horák; O. Parmová; S. Voháňka
Authors‘ workplace: Neurologická klinika LF MU a FN Brno
Published in: Cesk Slov Neurol N 2018; 81(5): 582-585
Category: Original Paper
doi: https://doi.org/10.14735/amcsnn2018582

Overview

Background:
Myotonia is a cardinal symptom of myotonic disorders. The most typical symptom of myotonia is a difficulty in releasing a forceful handgrip. It significantly deteriorates the quality of life to a degree that is disabling. Therefore, many drugs have been tested in myotonia therapy. One of the main issues of clinical trials has been the lack of a conclusive method for the quantification of myotonia. The aim of our study was translation and validation of the Myotonia Behaviour Scale (MBS). This scale was designed for subjective assessment of myotonia severity.

Methods:
Czech translation was approved by a professional translator and then validated through forward-backward translation. Repeatability and reproducibility were tested on a sample of 15 patients with myotonic dystrophy type 1 (MD1) and 25 patients with myotonic dystrophy type 2 (MD2). All patients completed one MBS form during a routine visit and a second one two days later.

Results:
The average MBS score was 2.5 in MD1 group and 1.7 in MD2 group. Correlation coefficients between the first and second completion were 0.965 in MD1 and 0.991 in the MD2 group, respectively. Correlation coefficients between relaxation time of handgrip and MBS score were 0.672 in MD1 and 0.627 in the MD2 group, respectively.

Conclusion:
MBS is a simple and quick scale suitable for long-term monitoring of patients with myotonia. We reported a significant correlation between MBS score and relaxation time of a forceful handgrip in both groups.

Key words:
myotonic dystrophy – myotonia – scale – questionnaire

The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study.

The Editorial Board declares that the manuscript met the ICMJE “uniform requirements” for biomedical papers

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