Bridging the gap: addressing NACC's evolving cognition batteries across UDS versions

The Uniform Data Set (UDS) version 3 neuropsychological battery replaced old tests used in UDS 1&2. Here, we validate domain scores for memory, executive functioning, and language co-calibrated across UDS eras.

We compared co-calibrated and harmonized domain scores to traditional equipercentile equating in a crosswalk sample. We also validated domain scores by evaluating associations with magnetic resonance imaging (MRI) findings and APOE genotype across UDS eras.

We co-calibrated cognitive domain scores for 49,396 participants, about 25% of whom had data spanning UDS 1&2 and UDS 3 eras. Crosswalk sample (n = 955) correlations between UDS 1&2 and UDS 3 domain scores and equipercentile scores were similar. Harmonized domain scores had statistically significant associations in imaging (n = 2458) and APOE validity assessments (n = 27,857). Significant differences in domain scores were found across UDS eras.

Longitudinal co-calibrated and harmonized cognitive domain scores bridge the gap across UDS versions and are available from the National Alzheimer's Coordinating Center.

Co-calibrated domain scores are validated in the NACC crosswalk sample. Co-calibrated domain scores are validated with neuroimaging measures. Co-calibrated domains scores are validated with APOE genotype. Co-calibrated domain scores reveal cognitive performance differences in enrollment visit depending on UDS era. Co-calibrated domain scores are readily available to investigators utilizing NACC's rich dataset.