Development and initial validation of the Cognitive Change Scale (CCS).

Background: Cognitive impairment is common in neurologic diseases. Precise measurement of cognitive change over time is necessary for isolating disease-related patterns from normal age-related decline. Existing measures of subjective cognition, however, focus on present status. There is, to our knowledge, no currently available self-report measure of cognitive change. We therefore developed the Cognitive Change Scale (CCS), which assesses perceived cognitive change in neurologic populations.

Methods: A systematic mixed-methods process was followed for the scale design and validation. Associations of CCS responses to demographics, mood, and fatigue were examined in 131 persons with multiple sclerosis. A total of 46 participants also completed a cognitive test battery. Correlations of test scores with CCS responses were calculated.

Results: The 17-item CCS showed good reliability and validity. Results of exploratory and confirmatory factor analyses supported a four-factor structure, with items reflecting change in (1) general cognition, (2) language and executive function, (3) external feedback, and (4) use of coping strategies. Positive relationships of CCS scores with fatigue, depression, and anxiety were observed. Correlations of CCS scores with cognitive test performance did not reach significance.

Conclusion: The CCS may be a useful cognitive outcome tool for treatment trials in neurologic populations.