AbstractBackgroundEarly, efficient identification of Alzheimer’s disease (AD) risk is a critical need. Dyadic subjective report from a participant and an informant/study partner (SP) who knows the participant well, may be a reliable and accurate method for assessing AD risk.MethodThe Caregiver and Study Partner Portal within the Brain Health Registry (BHR; an online registry and cohort) is a scalable tool for remotely obtaining dyadic data. All BHR participants are asked to identify a potential SP, who is invited to separately enroll and consent. SPs complete a demographic survey and questionnaires pertaining to cognition, behavioral symptoms, activities of daily living, and the health of the participant. Participants and SPs both complete an online adaptation of the Everyday Cognition Scale (ECog) to assess subjective cognitive change. We analyzed demographic characteristics of the dyads enrolled in BHR and measured correlation between SP and self‐report ECog scores. We used ADNI ECog data to estimate cut points likely to indicate cognitive impairment (1.43 for SP‐report scores and 1.65 for self‐report scores) and determined the number of BHR participants who are possibly impaired based on these cut points.ResultOut of 93,134 BHR participants, 10,494 (11.3%) have an enrolled study partner (Figure 1). The mean SP‐report ECog score is 1.35±0.50 and mean self‐report ECog score is 1.46±0.47. SP and self‐report ECog scores are correlated (r = 0.47, p < 0.001) (Figure 1). Out of 8,374 participants with available SP‐report ECog scores, 2,194 (26.2%) are possibly impaired. Out of 10,018 participants with available self‐report ECog scores, 2,384 (23.8%) of participants are possibly impaired (Figure 2).ConclusionThese findings demonstrate the feasibility of collecting online, dyad‐report demographic and subjective cognitive change data from a large cohort of participant‐SP dyads. The study failed to recruit an ethnoculturally and educationally diverse cohort of dyads. The positive correlation between self‐ and SP‐report ECog scores suggests dyad concordance in subjective report of change. Future efforts will focus on improving study partner enrollment and BHR task completion, increasing dyad diversity, and investigating the ability of remote dyadic measures to track cognitive decline and clinical progression along the AD continuum.