P1-540: MULTIDIMENSIONAL ITEM RESPONSE THEORY (IRT) FOR SURVEY HARMONIZATION AND DEMENTIA PREVALENCE PREDICTION IN THE GLOBAL BURDEN OF DISEASE (GBD) STUDY: AN EXAMPLE USING THE HEALTH AND RETIREMENT SURVEY (HRS)

Estimates of dementia prevalence from the Global Burden of Disease (GBD) study and other global meta-analytic efforts are limited by data sparsity, as they only consider sources that evaluate dementia prevalence. Large scale surveys that measure cognition and functional limitations are valuable sources of information, which could strengthen global prevalence estimates of dementia. We used data from the Health and Retirement Survey (HRS) and the...