Measurement properties of wheelchair use assessment tools in adults with autosomal recessive spastic ataxia of Charlevoix-Saguenay

Purpose: To establish the reliability and construct validity of two French-Canadian versions of assessment tools for manual (MWC) and powered wheelchair (PWC) users with autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS): the Wheelchair Skills Test Questionnaire (WST-Q-F) version 5.0 and the Wheelchair Use Confidence Scale (WheelCon-F) Short Form.

Methods: We recruited 32 MWC and PWC users with ARSACS aged between 34 and 64 years. Participants completed measures twice within 2 weeks for test-retest reliability and to determine the standard error of measurement. Construct validity was established by verifying hypothesized relationships between wheelchair use scores and other variables regarding personal factors, body functions, and activities. Participants' scores were also compared with those of MWC and PWC users with other diagnoses to explore known-groups validity.

Results: Adequate to excellent test-retest reliability values were found for all questionnaires (intraclass correlation coefficients between 0.506 and 0.995). SEMs were acceptable, ranging from 3.3 to 9.1 on the WST-Q-F and from 0.7 to 1.2 on the WheelCon-F. Moderate to excellent correlations supported construct validity for the WST-Q-F and the WheelCon-F. Compared with other populations, adults with ARSACS reported limited wheelchair skills, but similar wheelchair confidence.

Conclusions: The WST-Q-F and the WheelCon-F have excellent test-retest reliability, acceptable measurement errors, and support for construct validity in adults with ARSACS. This study was the first to evaluate these assessment tools in this population, and the results support a need to implement wheelchair skills training interventions in this population.IMPLICATIONS FOR REHABILITATIONThe WST-Q-F version 5.0 and the WheelCon-F Short Form are reliable and valid assessment tools to measure manual and powered wheelchair skills and self-efficacy in adults with autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS).The WST-Q-F version 5.0 and the WheelCon-F Short Form can be used to evaluate and describe wheelchair skills and wheelchair use self-efficacy in clinical practice and are recommended for future research in adults with ARSACS. These outcome tools may be especially useful to measure the effects of a wheelchair training program.