Assessing the Amount of Change in an Outcome Measure Is Not the Same as Assessing the Importance of Change

PURPOSE: To determine whether a difference exists between patients' self-ratings of amount of change and their self-ratings of importance of change. METHODS: Eighty-eight patients receiving treatment of low-back pain completed two global rating of change (GRC) scales 4 to 6 weeks after their initial assessments. The scales were similar in format, differing only in that one asked respondents about the amount of change and the other about the …