Abstract
Backgroundhere is a need for valid, disease-specific, caregiver-reported outcome measures that reliably assesses the symptomatic health of individuals across the Alzheimer’s disease continuum from mild cognitive impairment to dementia.
Aims: This research describes the development and validation of the Cognitive Impairment Caregiver Reported-Health Index (CICR-HI), a disease-specific, caregiver-reported outcome measure designed according to United States Food and Drug Administration (FDA) guidance to assess the point-in-time symptomatic burden of individuals with Alzheimer’s disease, mild cognitive impairment, and dementia.
Methods: Previous work identified the symptoms of greatest importance to individuals with cognitive impairment through caregiver qualitative interviews and a cross-sectional study. We selected symptomatic questions for potential inclusion in the CICR-HI based on their high importance to individuals with cognitive impairment. We conducted beta testing and test-retest reliability testing of the CICR-HI with caregivers of individuals with cognitive impairment to determine the usability and reliability of the instrument, its subscales, and its individual questions. Lastly, we determined the known groups validity and internal consistency of the final instrument.
Results: The validated CICR-HI measures eight symptomatic domains that are shown to be highly relevant to individuals with cognitive impairment. Beta testing with 12 caregivers revealed that the CICR-HI was highly relevant and easy to use. Test-retest reliability with 30 caregivers demonstrated a high intra-class correlation (0.801). Lastly, known groups analysis demonstrated that the CICR-HI is able to statistically distinguish between groups of individuals believed to have different levels of disease severity based upon demographic or clinical characteristics.
Conclusion: The CICR-HI is a regulatory-grade, disease-specific, caregiver-reported outcome measure capable of measuring disease burden across eight symptomatic domains in individuals with cognitive impairment. This instrument was developed and validated according to published FDA guidelines for use in clinical trials to serially measure how individuals with cognitive impairment feel and function. The CICR-HI adds to existing clinical trial infrastructure and provides a mechanism to quantify changes in multifaceted disease burden in cognitive impairment over time or in response to therapeutic intervention.