Since 1998, Zeng Yi launched and led (as Principal Investigator) the Chinese Longitudinal Healthy Longevity Survey (CLHLS), the largest longitudinal study of the oldest-olds with compatible younger-old in the world. The CLHLS aims to enhance healthy ageing, wellbeing and quality of life of older adults and families’ happiness in China and worldwide. It innovatively examines how the social, behavioral, environmental, and genetic factors and their interactions may influence healthy ageing.
To date, the CLHLS has conducted face-to-face interviews of 138.8 thousand participants in nine waves in 1998-2021. This project has received financial supports from global agencies, including the National Natural Sciences Foundation of China, National Social Sciences Foundation and Ministry of Science & Technology of China, U.S. National Institute of Aging, and United Nations Fund for Population Activities (UNFPA). It has also generated a large amount of seminal research on healthy ageing, as well as significant social impacts within and beyond China. The data of the CLHLS is now one of the most used free sources for scholars worldwide to conduct healthy ageing studies, based on which, researchers inside and outside China have published 17 books, 431 English papers and 731 Chinese papers, as well as 99 Ph.D. dissertations and 678 M.A. theses successfully defended.
Zeng Yi also leads the development of the ProFamy extended cohort-component method and the associated user-friendly software, which is widely used by scholars in various countries around the world to make projections on household trends and assess the consequences of changing household structures and population ageing. To date, scholars from 29 countries, UNFPA and World Bank have downloaded and used the ProFamy free software to do research on household and living arrangement projections for informed decision-making in socioeconomic planning and sustainable development under rapid population ageing.
Zeng Yi is broadly respected as a key policy advocator for China to change the one-child policy in order to better prepare for the population ageing. In recent years, he initiated a nationwide social practice program of “Respecting Aged and Caring for Children to Promote Intergenerational Assistance” and personally donated 1.0 million yuan to establish a fund for this initiative, which has progressed very well and obtained important social impacts. A role model for academics, Zeng Yi has made outstanding contributions to research and policy making in healthy ageing – for China and other countries around the world.