Spasticity
Outcome Measures in Spasticity Management
Outcome Measures in Spasticity Management
Susan H. Pierson, MD, PT
MF Brin, MD, editor
Muscle Nerve 1997; 20 (suppl 6): S36-S60.
Abstract: Development of validated and reliable outcome measures for spasticity rehabilitation has been hampered by the difficulty of quantifying functionally important parameters such as pain, ease of care, and mobility. Nonetheless, a combination of measures designed to assess technical and functional outcomes, patient satisfaction, and the cost effectiveness of treatment can be used together to evaluate status and track change in spasticity management, including treatment programs involving botulinum toxin. While double-blind, placebo-controlled studies remain the gold standard for clinical testing, the single-subject design is a useful alternative in many treatment protocols. Because no single tool can measure the many types of changes possible with treatment, the choice of assessment tools must be based on the functional changes expected from the treatment. A wide range of assessment tools are critically reviewed for their sensitivity, reliability, validity, and ease of administration.
©1997 John Wiley and Sons, Inc.
Key Points:
- A wide range of outcome measures exists for assessing spasticity and the effectiveness of intervention
- Most spasticity rating scales are ordinal
- Equal intervals between units on an ordinal scale cannot be automatically assumed
- Non-interval scaling can be addressed using Rasch analysis, though care must be taken to avoid inappropriate extrapolation
- Ratio scales, such as before/after measurements, are useful, reliable, and easy to administer
- A technical outcome is an expected change in a measurable variable, based on the technical goals of a procedure
- A functional outcome is an expected change in a patient's ability to perform a task
- Patient satisfaction measures are concerned with both the result and the process of care delivery
- Few clinical tests for spasticity have been validated
- The choice of test must be based on the change expected, and the sensitivity must match the range of expected improvement. Otherwise, the results will be meaningless
- The potential for a positive functional outcome following treatment depends on many factors besides spasticity, which must also be accounted for by the chosen outcome measures
- Changes in technical measures of spasticity may not correlate well with clinical improvement
- Because there is poor agreement among clinical spasticity scales, a comprehensive set of tests is needed to evaluate the effects of treatment
- The COPM is a useful measure for tracking both functional changes and patient satisfaction
