Cohort Profile: The China Health and Nutrition Survey--monitoring and understanding socio-economic and health change in China, 1989-2011

Abstract

This study began with the desire of the University of North Carolina (UNC), Chapel Hill (CH) Principal Investigator (PI) to be able to examine across space and time the ways economic and social change affected a range of health behaviours in a large country. China was selected because of its unique opening up of its economic and social system. In 1986 no longitudinal surveys existed in China and all surveys were either very narrow health, economic or demographic surveys. Furthermore, no raw data from any survey had been allowed out of the country. Since China's reform and open policy, the country was being transformed from one facing famine and extreme food shortages to one where the food supply addressed basic needs and the initial states of a major transformation of the food distribution and marketing system was occurring. With this as background, two UNC faculty members, Barry Popkin and Gail Henderson, a China scholar, began the process in 1986 of meeting a range of University and government officials to discuss this work. The Chinese Center for Disease Control and Prevention (CCDC) (formerly the Chinese Academy of Preventive Medicine, CAPM) was selected. The CCDC, under the leadership of Madame Chunming Chen, was very enthusiastic about the challenges of such an approach to understanding the interplay of socio-economic change and health and decided to invest the academy's own funds to collaborate on this initiative. An agreement that focused on publication, data ownership and data dissemination of the results was established. No funding agencies thought such an initiative could be undertaken and the data base obtained by the US institution for use and dissemination. As a result, a small grant of $60 000 from the Carolina Population Center (CPC) was the only available funding to initiate the first survey. The China Health and Nutrition Survey (CHNS) was established. The goal was to develop a multipurpose longitudinal survey that would allow the group to examine a series of economic, sociological, demographic and health questions of interest to the CAPM and these scholars. Professor John Akin joined Popkin and Henderson in work on the initial effort. Once the group proved able to collect the data and to get the raw data files out of China, a program project application was submitted to National Institute of Child Health and Human Development (NICHD) that included two additional waves of CHNS data collection. This was funded and all subsequent survey waves were funded by NICHD-funded R01s. Only later did the Chinese Ministry of Health decide the surveys were important, and the ministry instructed the collaborating provinces to place priority on long-term collaboration. The active involvement of the Minister of Health and others in the ministry has provided important political protection for the CHNS and also has provided continued counterpart partial financial support. Chinese colleagues are full and active partners in the CHNS project and have primary responsibility for data collection. Over the life of the project they have spent considerable time in CH working with the UNC–CH group on data analysis and training activities, and they plan to continue these efforts. Professors Keyou Ge, then Fengying Zhai, and now Bing Zhang lead the project for the CCDC. Professor Shuigao Jin, a statistician and computer expert, initially headed the component dealing with sampling and database development. Professor Huijun Wang is a key member of field work, data cleaning and data analysis. At one time Professor Shufa Du headed the project in China and now, as a faculty member at UNC, plays a major role in working with the CHNS. Part of the reason for the careful selection of the collaborator for the CHNS was the desire to insulate this study from the political and institutional problems that have hampered many subsequent survey research projects conducted jointly by US and Chinese institutions. By partnering as we have, we have been successful in continuing this survey during periods in China when many other western-funded social science-related surveys were discontinued. In 2009 the Department of Laboratory Medicine of China-Japan Friendship Hospital (CJFH), Ministry of Health (MOH) joined this project as the lead agency for the collection, storage and analysis of biospecimens. Dr Shengkai Yan leads the work related to biospecimens. This survey was designed to cover key public health risk factors and health outcomes, demographic, social and economic factors in depth at the individual, household and community levels. This in-depth survey collects data on occupations; incomes and benefits of working-age household members; time use; diet and nutritional status; activities of daily living, health status and use of health services; marriages, birth preference and pregnancies of reproductive-age women; mass media and body images; household size and composition; living arrangements; care of children and elders; housing condit