Purpose: Individuals with Huntington disease (HD) experience progressive cognitive decline that may appear years before motor manifestations of the disease. These declines have a profound effect on health-related quality of life (HRQOL) over the disease course, and thus it is important that self-report measures of cognitive function are validated for use in longitudinal studies. Methods: 359 individuals with premanifest or manifest HD completed baseline and at least one follow-up (12- and 24-month) assessment. Neuro-QoL™ Cognitive Function was administered at each time-point. Participants completed a self-reported global rating of cognitive change, as well as performance-based cognitive changes (using the Symbol Digit Modalities Test). Standardized response means (SRMs) and general linear models evaluated whether Neuro-QoL™ Cognitive Function was responsive to change over time with respect to self-reported and performance-based anchors. Test–retest reliability and known-group validity were also examined. Results: Responsiveness was supported by effect sizes that were small in magnitude, but in the expected direction relative to self-reported and performance-based change. General linear models generally supported 12- and 24-month responsiveness relative to self-reported cognitive change and 12-month responsiveness relative to performance-based change. Test–retest reliability was excellent, and the measure exhibited known-group validity. Conclusion: Longitudinal analyses generally indicate that the Neuro-QoL™ Cognitive Function measure is sensitive to change over time in individuals with HD. Neuro-QoL Cognitive Function changes reflect self-reported cognitive change at 12 and 24 months and performance-based change at 12 months. This measure may be useful in clinical trials or longitudinal observation studies.
- Huntington disease
- Longitudinal studies
- Outcome assessment (health care)
- Quality of life