Longitudinal Study of Aging Danish Twins, 1995

The focus of the "Longitudinal Study of Aging Danish Twins (LSADT)" was on elucidating the causes of variation in survival, health, diseases, loss of abilities, and cognitive functions among the elderly and oldest-old. The LSADT was conducted every two years between 1995 and 2005 and consists of six waves. The study is comprised of interviews of elderly Danish twins aged 75 years and older (later 70 years and older). At each interview wave, the interview assessment was based on the interview used in the previous waves, which covers health, physical functioning, cognitive functioning, depression symptomatology, social factors, lifestyle characteristics, and quality of life. The self-report interview assessments were supplemented with objective indicators of physical strength and agility, behavioral speed, and pulmonary peak-flow. Biological material was also collected from the participants for future DNA analysis.