The factor structure of the SF-36 in adults with progressive neuromuscular disorders.

Objective: Quality of life (QoL) is an important consideration in the care of patients with chronic neuromuscular disorder (NMD). The current study sought to determine the factor structure of the Medical Outcomes Study Short-Form 36 (SF-36) version 2 in patients with NMD to determine the appropriateness of using this instrument to assess QoL in this clinical population.

Methods: Confirmatory factor analyses were conducted on self-report SF-36 data from 245 individuals diagnosed with NMD. Six structural models of the SF-36 were evaluated against the participants' data.

Results: The underlying factor structure of the SF-36 in NMD was observed to be consistent with contemporary theoretical models of the instrument. However, the traditional measurement model of SF-36 performed comparatively poorly.

Conclusion: The use of the SF-36 in individuals with NMD can be recommended when eight sub-scales are used and reported. However, the suggestion that the SF-36 can be usefully used as a two-sub-scale measure of physical health and mental health components in this clinical group was not supported because of model fit limitations.