Reliability and validity of the power-mobility community driving assessment

The Power-Mobility Community Driving Assessment (PCDA) is a performance-based measure designed to assess driving performance of individuals using power wheelchairs or scooters in community environments. This article reports the results of pilot testing and an evaluation of the assessment's reliability and validity. Pilot testing was conducted with a random selection of Canadian occupational therapists working in the area of mobility. Although the response rate was very low, feedback confirmed the utility of the measure and contributed to one substantive scoring revision. Reliability and validity testing was conducted with a sample of 34 drivers. Internal consistency results were positive. Interrater reliability was fair to high but limited by the lack of variability in the scores. Construct validity hypotheses were tested on the relationships between PCDA scores and vision, perception, cognition, and environmental accessibility. Results indicated no relationships between the PCDA and perceptual and cognitive function and only a weak trend for a relationship with environmental accessibility. Concurrent validity was established: PCDA scores were positively associated with the judgments of therapists familiar with the driving performance of participants. In summary, the PCDA has moderate to good reliability, and content and concurrent validity results were found. More research is needed, particularly on the underlying constructs of successful driving performance. At this point, rehabilitation professionals and their clients are urged to use this assessment to establish driving performance rather than relying on assessments of perception, cognition, or environmental accessibility to predetermine whether someone will receive power mobility. Clinicians may find this a useful tool to identify where clients are able to drive safely in community settings, to identify specific learning needs, and, through those, to promote independent living for drivers of power-mobility devices.