The National Institute on Aging’s (NIA) Baltimore Longitudinal Study of Aging (BLSA), the world’s most comprehensive and longest running study of aging, collects data on the physical and cognitive status of 1,300 older adults at regular intervals.

As the study has proceeded, some participants have moved out of the Baltimore area, or have experienced physical problems and/or mental decline that prevent them from visiting the study clinic for scheduled health evaluations. The potential for loss of valuable information about the aging process due to missed study clinic visits was the impetus for the NIA to request developing a program to continue data collection on study participants in their homes.