Interrater and intrarater reliability of the wheelchair skills test version 4.2 for power wheelchair users

Purpose: The purpose of this study is to estimate the interrater and intrarater reliability of the Wheelchair Skills Test (WST) Version 4.2 for powered wheelchairs operated by adult users. Materials and methods: Cohort study with a convenience sample of occupational therapists (n = 10). For the main outcome measure, participants viewed and scored eight videos of adult power wheelchair users completing the 30 skills of the WST Version 4.2 on two occasions, a minimum of two weeks apart. Using these scores, we calculated intraclass correlation coefficients to estimate interrater and intrarater reliability. Results: The interrater reliability intraclass correlation coefficient was 0.940 (95%CI 0.862-0.985). Intrarater reliability intraclass correlation coefficients ranged from 0.923 to 0.998. Conclusions: The WST Version 4.2 has excellent interrater and intrarater reliability and is a reliable tool for use in clinical and research practice to evaluate a power wheelchair user's skill capacity.