Survey Design

The survey covers 9 provinces that vary substantially in geography, economic development, public resources, and health indicators. A multistage, random cluster process was used to draw the sample surveyed in each of the provinces. Counties in the 9 provinces were stratified by income (low, middle, and high) and a weighted sampling scheme was used to randomly select 4 counties in each province. In addition, the provincial capital and a lower income city were selected when feasible. In two provinces, other large cities had to be selected.  Villages and townships within the counties and urban and suburban neighborhoods within the cities were selected randomly. In 1989-1993 there were 190 primary sampling units, and a new province and its sampling units were added in 1997.  Currently there are about 4,400 households in the overall survey, covering some 19,000 individuals.  Follow-up levels are high, but families that migrate from one community to a new one are not followed.  Movement within the primary sampling units and some larger urban entities is attempted.

The first round of the CHNS, including household, community, and health/family planning facility data, was collected in 1989. Six additional panels were collected in 1991, 1993, 1997, 2000, 2004, and 2006. Since the 1993 survey, all new households formed from sample households have been added. Since 1997, new households in original communities have been also added to replace households no longer participating in the study. Also since 1997, new communities in original provinces have been added to replace sites no longer participating. A new province was also added in 1997 when one province was unable to participate.  The dropped province returned to the study in 2000.

The Chinese Ministry of Public Health has committed itself to continuing this project as long as outside support is provided to supplement the extensive support it already provides. The project is truly a collaborative effort; funding is shared equally by the American and Chinese institutions and there is considerable sharing of expertise and other skills, resulting in significant collaborative research.

Household Survey

A complete household roster is used as a reference for subsequent blocks of questions on time allocation at home (e.g., child care, elderly care, other key home activities) and economic activities. Questions on income and time allocation probe for any possible activity each person might have engaged in during the previous year, both in and out of the formal market. Information on water sources, construction and condition of the home, and on ownership of consumer durables is gathered from the respondent. Additional questions probe for all possible items the household might own. Full income from market and non-market activities can be imputed. The detailed estimation of income that will be possible using these data represents a significant advance in the measurement of income in China. Inclusion of non-monetary government subsidies such as state-subsidized housing is an especially important advance.

Health Services

The health services section contains detailed data on insurance coverage, medical providers, and health facilities that the household might use under selected circumstances. Questions about accessibility, time and travel costs, and perceived quality of care are asked. Information on illnesses and on all uses of the health system during the previous month is collected for children below age 7 and for adults between ages 20 and 45 in 1989, and from all household members in later years. Questions on immunizations, use of preventive health services, and use of family planning services are also asked.

Individual Survey

Since 2004, all questions related to individual activities, life style, health status, marriage and birth history, body shape and mass media exposure, etc, have been moved to two sets of individual questionnaires: for adults aged 18 and older and for children and adolescents aged from 0 to under 18. Time allocation on household chores and child care, physical activities, and soft drink and sugared fruit drink consumption are asked for children aged 6 and above and all adults. Smoking, tea, coffee and alcohol consumption, and diet and activity knowledge are asked for youth aged 12 and older and all adults. Body shape conceptions are asked for adolescents aged 12 and older only, but mass media questions are asked for adolescents aged 12 and older and ever-married women under age 52 with children aged 6-18 in the household. Marriage, pregnancy and birth history, and inter-generational linkages to parents and parents-in-law are asked for ever-married women under age 52. Activities of daily living and memory test ask asking for adults aged 55 and older.

Nutrition & Physical Examination

Three days worth of detailed household food consumption information was collected. In addition, individual dietary intake for three consecutive days was collected for every household member, irrespective of age or relationship to the household head. Adults and children received detailed physical examinations that included weight, height, arm and head circumference, mid-arm skinfold measurements, and blood pressure (for kids aged 7 and older and all adults). Limited clinical nutrition and physical functioning data was collected since 1993. Activities of daily living and related information for older adults and a new set of physical activity and inactivity data were added for all respondents since 1997.

Community Survey

The community questionnaire (filled out for each of the primary sampling units) collects information from a knowledgeable respondent on community infrastructure (water, transport, electricity, communications, and so on), services (family planning, health facilities, retail outlets), population, prevailing wages, and related variables.

Food Market Survey

In the first two surveys, state and free market data were collected. But by 1997, none of our communities had separate state prices, so only free market stores and large stores were visited from then onward. In all cases, prices were collected for a representative basket of commodities.

Health and Family Planning Facility

In 1989, 1991 and 1993, separate visits were made to obtain in-depth data in each community for every identified health service and family planning provider or facility. Information was collected concerning personnel, sources of funds, services available, prices (asked separately for insured and self-pay patients), and distance to the primary sampling units served by the facility. A separate questionnaire was administered to the local family planning official about family planning policies in the community. These were discontinued in 1997, but selected questions were asked of these same personnel as part of the community questionnaire since then.