Article

The Spinal Cord Independence Measure -
Self Report (SCIM-SR) is a
self-report instrument for assessing functional independence of persons with
spinal cord injury. This study examined the internal construct validity and
reliability of the SCIM-SR, when administered in a community survey, using the
Rasch measurement model. METHODS: Rasch analysis of data from 1,549 individuals
with spinal cord injury who completed the SCIM-SR. RESULTS: In the initial
analysis no fit to the Rasch model was achieved. Items were grouped into testlets
to accommodate the substantial local dependency. Due to the differential item
functioning for lesion level and degree, spinal cord injury-specific sub-group
analyses were conducted. Fit to the Rasch model was then achieved for individuals
with tetraplegia and complete paraplegia, but not for those with incomplete
paraplegia. Comparability of ability estimates across sub-groups was attained by
anchoring all sub-groups on a testlet. CONCLUSION: The SCIM-SR violates certain
assumptions of the Rasch measurement model, as shown by the local dependency and
differential item functioning. However, an intermediate solution to achieve fit
in 3 out of 4 spinal cord injury sub-groups was found. For the time being,
therefore, it advisable to use this approach to compute Rasch-transformed SCIM-SR
scores.

Langue : ANGLAIS