| The purpose of this study was to develop the Functioning Everyday with a Wheelchair - Capacity (FEW-C), a valid and reliable performance-based observation tool to measure the effects of wheeled mobility and seating interventions on functional capabilities specific to consumers needs. The tool was modeled after the Functioning Everyday with a Wheelchair (FEW), a companion self-report measure and characteristics of the capacity qualifier of the World Health Organization International Classification of Functioning, Disability, and Health. Prior to the development of the tool a systematic review of the scientific literature revealed limited availability of performance based measures of functional outcome that could be applied across the spectrum of wheeled mobility and seating devices or types of impairments. Excellent interrater reliability coefficients (ICC 2,k = 0.98) were established with 13 wheeled mobility and seating device users and 8 trained raters. Internal consistency of the FEW-C, based on a sample of 25 wheeled mobility and seating device users, yielded Cronbach's alphas ranging from 0.74 to 0.89 indicating good internal consistency without redundancy. Multitrait-multimethod matrix analyses, yielded fair to good convergent and discriminant validity when compared with other tools that were measuring similar traits by different methods. A non-randomized clinical trial was implemented to test the ability of the performance-based FEW-C to detect statistical and practical change over time, and to ascertain if the FEW-C results differed from the companion self-report tools. Findings indicated that the FEW-C and other self-report tools were able to measure practical changes in function over time with very large Cohen's d effect sizes (2.28-3.18) following the provision of a new wheeled mobility and seating device, however, each of the tools behaved differently. These findings further confirmed the effectiveness of the wheeled mobility and seating interventions provided by the clinicians. Our findings also indicated that the operationalization of the items of the reliable and valid FEW self-report tool into a performance-based observational tool yielded another reliable and valid tool for gathering data about functioning with a wheeled mobility and seating device, and that each tool contributed unique information to wheeled mobility and seating assessments. |
