1) Evaluate the association of self- and study-partner report of subjective cognitive decline (SCD) to objective cognitive performance across ethnoracial groups. 2) Evaluate the concordance of self- and study partner report of SCD across ethnoracial groups.

Participants were 5241 non-Hispanic White (NHW), 267 non-Hispanic Black (NHB), 225 Hispanic, and 228 Asian participants screened for the A4 study (N=5961). Participants completed the Preclinical Alzheimer Cognitive Composite (PACC), and self- and study partner-report of SCD using the Cognitive Function Index (CFI). Analysis of variance was used to assess difference in key variables by ethnoracial group. Regression analyses were conducted to evaluate the association of SCD and objective performance by ethnoracial group, and the association between self-and study partner report of SCD by ethnoracial group.

Asian participants reported the highest mean CFI relative to all other groups, while NHW reported the lowest (F(3,5957)=41.93, p <.001). Asian and NHW participants had higher PACC scores relative to NHB and Hispanic participants (F(3,5957)=41.93, p <.001). Regression analyses revealed higher CFI was associated with lower PACC score across groups, and this association was strongest in the Asian sample relative to other groups (F(10, 5897)=40.49, p<.001,R2=.06). Evaluation of study partner characteristics suggested NBH participants had the highest proportion on non-spousal study partners relative to other groups. Regression analyses revealed no differences in the association of self- and study partner report of SCD across ethnoracial groups (F(10, 5859)=132.9, p<.001, R2=0.18).

Results suggest that that SCD is associated with objective cognitive performance across racial groups, although the strength of this association appears to vary in this sample. There is also consistent concordance between self- and study partner report of SCD across groups, despite differences in study partner relationships. SCD may be considered a valid predictor of subtle cognitive change across groups in the A4 sample. Limitations include small group sizes relative to the large NHW sample. Future work with larger, more representative samples are needed to further validate these findings.