Measurement of mobility following stroke: a comparison of the Modified Rivermead Mobility Index and the Motor Assessment Scale

Background and purpose The Modified Rivermead Mobility Index (MRMI) is a newly developed outcome measure that aims to evaluate the effectiveness of physiotherapy on mobility following stroke. Any new measurement tool requires extensive testing of its validity and reliability before it can be recommended for use in clinical practice or research. The purpose of this study was to investigate the concurrent validity of the MRMI when measuring mobility in patients who have had a stroke. The internal consistency and test administration times of the MRMI and Motor Assessment Scale (MAS) were also investigated.

Methods Twenty-six hospitalised acute/sub-acute stroke patients from the Medical and Elderly wards of a General Hospital in West Yorkshire were assessed independently with the MRMI and MAS. Test administration time was also recorded.

Results Limits of agreement indicated that on average subjects scored three points higher on the MRMI than the MAS (mobility-related items). Ninety-five percent of subjects scored between one point lower and seven points higher on the MRMI than the MAS. Both scales possessed high internal consistency (MRMI α=0.949 and MAS α=0.953). Individual items also possessed high internal consistency (MRMI α=0.743–0.959, MAS=0.854–0.893) except the sitting balance items (MRMI α=0.304 and MAS α=0.545). Both scales took an average of 17min to administer.

Conclusions The mean difference between scores on the MRMI and MAS was small enough to allow clinicians to use either scale to measure mobility in stroke patients. Both scales possessed high internal consistency except the sitting balance items that may be measuring a different construct to mobility. The MRMI and MAS are sufficiently quick to administer to advocate use in routine clinical practice.