RELIABILITY AND VALIDITY OF THE WHEELCHAIR USERS SHOULDER PAIN INDEX (WUSPI)

Many long term wheelchair users develop shoulder pain. The purpose of this study was to examine the reliability and validity of the Wheelcha ir User's Shoulder Pain Index (WUSPI), an instrument which measures sh oulder pain associated with the functional activities of wheelchair us ers. This 15-item functional index was developed to assess shoulder pa in during transfers, self care, wheelchair mobility and general activi ties. To establish test-retest reliability, the index was administered twice in the same day to 16 long term wheelchair users and their scor es for the two administrations were compared by intraclass correlation . To establish concurrent validity, the index was administered to 64 l ong term wheelchair users and index scores were compared to shoulder r ange of motion measurements. Results showed that intraclass correlatio n for test-retest reliability of the total index score was 0.99. There were statistically significant negative correlations of total index s cores to range of motion measurements of shoulder abduction (r = -0.48 5), flexion (r = -0.479) and shoulder extension (r = -0.304), indicati ng that there is a significant relationship of total index score to lo ss of shoulder range of motion in this sample. The Wheelchair User's S houlder Pain Index shows high levels of reliability and internal consi stency, as well as concurrent validity with loss of shoulder range of motion. As a valid and reliable instrument, this tool may be useful to both clinicians and researchers in documenting baseline shoulder dysf unction and for periodic measurement in longitudinal studies of muscul oskeletal complications in wheelchair users.