Behavioural Surveillance Surveys - The Wisdom of Whores

Step 7 : Constructing a
sampling frame
The process of constructing sampling
frames can be simple or complicated,
depending on the nature of the sub-population
and the details of the sampling approach.
In some instances the lists for the different
stages of sampling may be readily available.
For example, a survey of in-school youth
might use lists of schools separated by gender
and with measures of size for the number of
students in each school and in each class,
which can be obtained through the ministry of
education. On the other hand, consider the
case of a survey with commercial sex workers.
A list of establishments where the sex workers
solicit clients may be required, along with an
estimate of the number of sex workers who
are likely to frequent the establishments on
different nights of the week. Such a sampling
frame would require a significant amount of
up-front fieldwork, which must be anticipated
in the budget and timeline. This type of
fieldwork might also require specialized
personnel, often drawn from the respondent
group itself. Adequate time and resources
for sampling frame development are a frequent
omission of survey protocols. Detailed
information on mapping and sampling frame
development is contained in Chapter 3
of these guidelines.
Step 8 : Develop the sampling
design
The sampling design for a given survey
effort defines the universe and domains for the
survey, the sample size requirements, the
number and size of clusters and other major
steps of the sampling strategy. In addition,
the procedures to be used to estimate
population parameters from the sample data
and to calculate estimates of sampling errors
should also be specified as part of the sample
design. The sampling plan describes how
the sampling design will be implemented ;
and provides step-by-step instructions to be
followed in choosing survey respondents.
Developing the sampling design is a
technical exercise, requiring estimates of
existing levels of risk behavior, decisions
about the magnitude of changes worth
measuring, and the accuracy with which
they should be measured. All of these
aspects are described in detail in Chapter 4.
Step 9 : Develop the survey
protocol
A survey protocol lays out the research
methodology to be used for the survey.
It includes a description of the goals and
objectives of the research, as well as details
about the methodology including a description
of the chosen target populations and sites,
and a sampling plan for each sub-population.
Questionnaires to be used by field staff in
conducting interviews with survey respondents,
plus auxiliary materials such as interviewer
guides used both for training purposes and as
an on-site reference for field staff would also
be part of the protocol. In some surveys,
supervisory guides are also prepared in order
to standardize supervision of the fieldwork.
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C H A PTER 2 B EHAV I OR A L S U R V EI L L A NC E S U R V EY S