Related Experiment Video
Updated: May 24, 2026
Using a Real-Time Locating System to Measure Walking Activity Associated with Wandering Behaviors Among Institutionalized Older Adults
Published on: February 8, 2019
Multi-group measurement invariance of the multiple sclerosis walking scale-12?
Robert W Motl1, Sean Mullen, Edward McAuley
1University of Illinois at Urbana-Champaign, Urbana, IL, USA. robmotl@illinois.edu
Objective:
One primary assumption underlying the interpretation of composite multiple sclerosis walking scale-12 (MSWS-12) scores across levels of disability status is multi-group measurement invariance. This assumption was tested in the present study between samples that differed in self-reported disability status.
Method:
Participants (n = 867) completed a battery of questionnaires that included the MSWS-12 and patient-determined disease step (PDDS) scale. The multi-group invariance was tested between samples that had PDDS scores of ≤2 (i.e. no mobility limitation; n = 470) and PDDS scores ≥3 (onset of mobility limitation; n = 397) using Mplus 6·0.
Results:
The omnibus test of equal covariance matrices indicated that the MSWS-12 was not invariant between the two samples that differed in disability status. The source of non-invariance occurred with the initial equivalence test of the factor structure itself.
Conclusion:
We provide evidence that questions the unambiguous interpretation of scores from the MSWS-12 as a measure of walking impairment between samples of persons with multiple sclerosis who differ in disability status.
