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Population Studies: State-of-the-art protocol (Milestone 1.D)


Timeline Start - End

2018 - 2023

Research Implementation Area

Population Studies and Precision Medicine

Develop state-of-the-art protocol for assessing dementia on large nationally representative samples that (a) includes racial/ethnic subsamples large enough to support disparities research and (b) is adaptable for use in comparable studies around the world

Success Criteria

  • Archive and share data for use by the research community.

  • Update national estimates of the prevalence and incidence of dementia and cognitive impairment as well as address important questions about the epidemiology and population impact of dementia. Repeat national estimates in 2021 to measure trend in dementia prevalence.

  • Support research projects comparing international differences to identify potential risk and protective factors. 

  • Support research on health disparities by racial/ethnic groups.

  • Use existing cohort studies to investigate critical periods for intervention success, including cohorts well before mid-life.

Summary of Key Accomplishments

The success criteria for this milestone have been achieved. NIA supported the development of a state-of-the-art protocol for assessing dementia in large nationally representative samples – called the Harmonized Cognitive Assessment Protocol (HCAP) – which is now being implemented in the NIA-funded Health and Retirement Study and multiple international “sister studies.” The HCAP enables researchers to measure and understand dementia risk in ongoing longitudinal studies of aging around the world using methods and content that are as similar as possible across studies. 

The key accomplishments summary is current as of March 2022. 

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