Chinese Longitudinal Healthy Longevity Survey (CLHLS), [China], 1998-2018

The Chinese Longitudinal Healthy Longevity Survey (CLHLS) provides information on health status and quality of life of the elderly aged 65 and older in 23 provinces of China from 1998 to 2018. The study was conducted to shed light on the determinants of healthy human longevity and oldest-old mortality. To this end, data were collected on a large percent of the oldest population, including centenarians and nonagenarians; the CLHLS provides information on the health, socioeconomic characteristics, family, lifestyle, and demographic profile of this aged population.
The questionnaire data collected provides information on family structure, living arrangements and proximity to children, activities of daily living (ADL), the capacity of physical performance (picking up a book from the floor; standing up from a chair; turning 360 degrees without help), self-rated health, self-evaluation of life satisfaction, cognitive functioning, chronic disease prevalence, care needs and costs, social activities, diet, smoking and drinking behaviors, psychological characteristics, economic resources, and care giving and family support among elderly respondents and their relatives. Information about the health status of the CLHLS participants who were interviewed in the previous wave but died before the current survey was collected by interviewing a close family member, and includes information such as cause of death, chronic diseases, ADL before dying, frequency of hospitalization or instances of being bedridden from the last interview until death, whether bedridden before death, length of disability and suffering before death.
For the participants from the in-depth study sites of the 8 longevity areas, in
addition to the questionnaire interview data, the CLHLS conducted lab tests of
the biomarkers using blood/urine samples collected from the voluntary
participants as well.