Reliability and validity of upper limb short questionnaire for Duchenne muscular dystrophy

Abstract

Purpose

In patients with Duchenne muscular dystrophy (DMD), weakness of the upper limb (UL) muscles has a significant impact on daily activities and body functions. This problem necessitates a screening tool that can be used quickly and easily in clinical situations, such as the Upper Limb Short Questionnaire (ULSQ). However, its validity and reliability as a clinical measure have not yet been evaluated.

Materials and methods

The ULSQ was initially administered in face-to-face interviews, and then by telephone four weeks later. Lower limb and UL body functions were assessed by the Vignos and modified Brooke scales, respectively.

Results

A total of 160 patients participated in the initial ULSQ interview; 132 patients completed the follow-up interview. Construct validity was confirmed by exploratory and subsequent confirmatory factor analyses. The UL function component sum score correlated with the modified Brooke scale score (Kendall’s Tau 0.64, p < 0.001). The total and component (UL function, pain, and stiffness) sum scores were higher in non-ambulators than in ambulators. The reliability was acceptable, as determined by internal consistency and test-retest agreement.

Conclusion

The ULSQ is a valid and reliable measurement tool for screening UL function, pain, and stiffness in patients with DMD in clinical settings.

IMPLICATIONS FOR REHABILITATION

• The Upper Limb Short Questionnaire (ULSQ) for patients with Duchenne muscular dystrophy (DMD) can be easily used in clinical settings.

• The ULSQ comprises 14 items that assess upper limb function, pain, and stiffness in patients with DMD and is a valid and reliable assessment tool for screening purposes.

• The sum score of the upper limb function component (ULSQ 1–5; 1 point per item) could be used to measure activity limitations.

Keywords:

• Duchenne muscular dystrophy
• Factor analysis
• Function
• Pain
• Stiffness
• Upper limb

Acknowledgment

We gratefully acknowledge the effort of Yale Kim, a physical therapist.

Disclosure statement

The authors declare that they have no competing interests. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Additional information

Funding

The study was approved by Seoul National University Hospital Institutional Review Board [IRB no. 1810-120-982].