Future Directions for the HRS Harmonized Cognitive Assessment Protocol

In the absence of effective pharmacological treatment to halt or reverse the course of Alzheimer’s disease and related dementias (ADRDs), population-level research on the modifiable determinants of dementia risk and outcomes for those living with ADRD is critical. The Harmonized Cognitive Assessment Protocol (HCAP), fielded in 2016 as part of the U.S. Health and Retirement Study (HRS) and multiple international counterparts, has the potential to play an important role in such efforts. The stated goals of the HCAP are to improve both our ability to understand the determinants, prevalence, costs, and consequences of cognitive impairment and dementia in the U.S. and to support cross-national comparisons. The first wave of HCAP demonstrated feasibility and value of the more detailed cognitive assessments. To achieve its full potential, we recommend that the HCAP: 1) increase the representation of racial/ethnic minority participants disproportionately affected by ADRDs, 2) administer the HCAP repeatedly and with greater frequency to facilitate longitudinal analyses, cross-national harmonization, and precise characterization of practice and period effects, 3) field a clinical dementia assessment for at least a subset of HCAP participants, 4) phase-in a baseline assessment for people under age 60 in order to facilitate research on the earlier stages of cognitive impairment and midlife dementia prevention, 5) consider dropping lower performing items from the HCAP to increase feasibility of scaling the assessment to more participants at more frequent intervals, 6) enhance the documentation, multi-lingual options, training activities, and randomized sub-studies of language effects or other tools to promote the use of the HCAP and cross-national comparisons, 7) incorporate blood-based AD biomarkers, and 8) improve the capacity of the HCAP to understand the consequences of dementia, including for caregivers and for policy-relevant outcomes such as use of home and community-based services. We believe that the capacity of the HCAP to achieve its stated goals will be greatly enhanced by considering these changes and additions.