Behavioural Surveillance Surveys - The Wisdom of Whores

3. Choosing populations for behavioral
surveillance
Chapter 3 describes how to go about
choosing the appropriate sub-populations for
behavioral surveillance. This process will be
guided by the epidemic situation in a country,
and the needs of prevention programs.
Feasibility and other issues are also considered.
This chapter will be of interest to those who
are responsible for the output of surveillance
systems and the use of the data they generate.
4. Sampling
Appropriate sampling is absolutely critical
to ensuring that BSS generates information that
provide a reliable picture of trends over time.
Most countries have a great deal of expertise
in solid sampling methods for household
surveys (such as Demographic and Health
Surveys). However these methods are
inappropriate for sub-populations of interest
to HIV prevention programmers, such as sex
workers or injecting drug users. Chapter 4
therefore gives detailed information about
sampling methods appropriate in different
situations, and their implications for interpreting
results. It will be most useful to those
who are actually implementing the surveys,
as well as those engaged in the technical
analysis of the data.
5. Analysis issues related to multi-stage
cluster sampling
This chapter deals with how to weight
data at the analysis stage to compensate for
limitations of the sampling design. It provides
information for technical staff who will be
designing the sampling frame and conducting
the analysis.
6. Selecting and adapting questionnaires
These guidelines include a number of
standardized questionnaires intended for use
with different sub-populations. This chapter
discusses when to use which questionnaire,
and how to adapt it for local use. Other
issues surrounding the interview and data
collection process are discussed.
7. Data analysis
The reliability of the information generated
by BSS will depend largely on appropriate
sampling and high quality data collection.
But the way the data are analyzed can also
have a major impact on its reliability and its
credibility. Chapter 7 describes how data can
be analyzed and presented for maximum
credibility, and gives examples from BSS in
various countries. It includes information
about the basic tests of statistical significance
needed to demonstrate that changes over time
are not just random fluctuations. This section
will be most useful to the technical staff who
are conducting the data analysis.
8. Data use
Information is only as valuable as the use
to which it is put. Chapter 8 recaps briefly
some of the major uses of information generated
by BSS. It also suggests ways of presenting
information to different audiences in ways that
will encourage them to act to strengthen the
response to HIV. This section provides
information that should help public health
officials maximize the benefit of the information
they have taken the trouble to generate.