Towards a short questionnaire for stepwise assessment of upper limb function, pain and stiffness in Duchenne muscular dystrophy

Abstract

Purpose: Duchenne muscular dystrophy can lead to upper extremity limitations, pain and stiffness. In a previous study, these domains have been investigated using extensive questionnaires, which are too time-consuming for clinical practice. This study aimed at gaining insight into the underlying dimensions of these questionnaires, and to construct a short questionnaire that can be used for clinical assessment.

Methods: Exploratory factor analysis was performed on the responses of 213 participants to a web-based survey to find the underlying dimensions in the Capabilities of Upper Extremity questionnaire, the ABILHAND questionnaire, and questionnaires regarding pain and stiffness. Based on these underlying dimensions, a stepwise approach was formulated. In addition, construct validity of the factors was investigated.

Results: In total, 14 factors were identified. All had high internal consistency (Cronbach's alpha >0.89) and explained 80–88% of the variance of the original questionnaires. Construct validity was supported, because participants in the early ambulatory stage performed significantly better (p< 0.001) than participants in the late non-ambulatory stage.

Conclusion: The factors identified from the set of questionnaires provide a valid representation of upper extremity function, pain and stiffness in Duchenne muscular dystrophy. Based on the factor commonalities, the Upper Limb Short Questionnaire was formulated.

Implications for Rehabilitation

• New insights into the underlying dimensions of upper extremity function, pain and stiffness in Duchenne muscular dystrophy are gained.

• Fourteen factors, with good internal consistency and construct validity, are identified regarding upper extremity function, pain and stiffness in Duchenne muscular dystrophy. Based on these factors, the Upper Limb Short Questionnaire is presented.

• The Upper Limb Short Questionnaire can be used as an identifier of arm-hand limitations and the start of more thorough clinical investigation.

Keywords:

• Duchenne muscular dystrophy
• factor analysis
• pain
• stiffness
• upper extremity
• upper limb short questionnaire

Acknowledgements

The authors would like to acknowledge Jan CM Hendriks, PhD, statistician, for his help with the statistical analysis and interpretation of the data collected during this study. We also would like to thank all of the participants for filling out the questionnaire used in this study, and we would like to acknowledge the Duchenne patients’ organizations worldwide for distributing the questionnaire to their members. This research was supported by the Dutch Technology Foundation STW (which is part of the Netherlands Organization for Scientific Research (NWO), and which is partly funded by the Ministry of Economic Affairs), UPPMD, Prinses Beatrix Spierfonds, Spieren voor Spieren, Johanna Kinderfonds, Kinderrevalidatiefonds Adriaanstichting, Focal Meditech, OIM Orthopedie, Ambroise, and Flextension.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.

Additional information

Funding

This work was supported by the NWO Domain Applied and Engineering Sciences (AES (in dutch: TTW)) under grant number 11832.