J Rheumatol
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A proposed standard "core set" of outcome measures for low back pain includes 5 domains: back-specific function, generic health status, pain, work disability, and patient satisfaction. This paper focuses on the 2 recommended back-specific measures of function: the Roland-Morris Disability Questionnaire (RDQ) and the Oswestry Disability Index (ODI). We specifically address their ability to measure change. ⋯ The responsiveness of the RDQ found in the literature ranges from 2 to 8 points on its 0 to 24 scale depending on what change is being measured. As a rough guide, Roland recommends that a change in 2-3 points on the RDQ should be considered the minimum clinically important change. Choosing any value larger than 5 in designing a clinical trial would risk underpowering the trial, since fewer patients are needed if a trial is designed on the basis of a large change score.