The 90+ Study is one of the largest studies of the oldest-old in the world. More than 1,600 people have enrolled. Initial participants in The 90+ Study were once members of The Leisure World Cohort Study (LWCS), which was started in 1981. Participants of The 90+ Study are visited every six months by researchers who perform neurological and neuropsychological tests. Our researchers at the Clinic for Aging Research and Education (CARE), located in Laguna Woods, obtain information about diet, activities, medical history, medications and numerous other factors. Additionally, participants are given a series of cognitive and physical tests to determine how well people in this age group are functioning.