The Role and Scope of Private Medical Practice in China

Chapter 2. Methodology
Selection of District/Township
Two urban districts and two rural townships from each city or county
respectively were then randomly selected from a list of all districts/townships,
arranged from the biggest to the smallest according to population size, as follows:
Cumulative population was computed for both lists, from the first district/township to
the last. The first district (for city) or township (for county) respectively was selected
based on the cumulative population that was closest to a random number generated.
The second district or township respectively was selected based on the cumulative
population which was closest to the midpoint between the first district/township
chosen and the final cumulative population. The names of the two districts or
townships were then affirmed by the local health department.
Selection of residential area
Residential areas were defined according to the residential committees in
charge of these areas. Within each city or county, two urban residential committees
and two rural village committees were randomly selected. The method of the selection
was the same as for the district or township. The households under the jurisdiction of
the residential/village committee would constitute the cluster of households to be
studied.
Selection of household
The target sample population was 150 households from the total number of
households within the jurisdiction of each residential committee or village committee.
To cater for non-response, 180 households were randomly selected from each, as
follows:
The list of households was compiled based on house number, block, and/or
known size of family. As the total number of families in the community or village was
known, the sampling interval was determined by dividing the number of families by
180. The first household was selected on the basis of a computer-generated random
number. The rest of the households were then determined according to the sampling
interval. The names of heads of households and their addresses were then recorded.
The last 30 households were designated as “reserve households”, for replacing nonresponding
households if necessary. No replacements were used once the number of
households interviewed had reached 150.
Selection of respondent
One respondent per household was interviewed. The inclusion criteria were:
living in the household, regardless of residential registration; either male or female;
and 18 years and older. The exclusion criteria were: below 18 years of age; mentally
or cognitively impaired; too sick or weak to answer questions; unable to answer
questions because of other reasons, e.g. physical impairments; and inability to use
mandarin or for any other reason, unable to communicate with interviewer.
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