Guidelines for second generation HIV surveillance - World Health ...

4.2.1. Use behavioural data to know your epidemic
It is well known that some sexual or drug use behaviours are risk factors for acquiring HIV. Thus, many
interventions were put in place to address these behaviours either at the individual level or at the population
level, or to break structural barriers to facilitate behaviour change.
Tracking risk behaviours is essential for predicting HIV trends. In many ways, tracking behavioural trends
is a more timely reflection of current epidemic patterns than HIV prevalence trends, because behavioural
patterns can show the potential for HIV transmission by population group and location.
4.2.2. Bias in behavioural data
In addition to selection bias, a common form of bias in behavioural data is social desirability bias. This type
of bias reflects the self-reported nature of behavioural data.
Respondents in a survey describe their own levels of behaviour. Individuals may overreport safe behaviours
to avoid judgement by the person interviewing them. Respondents engaged in an intervention programme
know the right answers when asked:
• Do you use condoms
• Have you used a condom during the last intercourse with a sex worker
• Do you use sterile injecting equipment
• How many sexual partners do you have
It is difficult to confirm these self-reports through other sources, which complicates the interpretation of
behavioural trend data. However, there are recommended methods to reduce social desirability bias in
behavioural data.
Increasingly, the sources of quantitative behavioural trend data come from probability surveys. As with
other surveys, there is a need to understand the representativeness and potential selection biases of the
data before being able to interpret results. Different methodologies (self-administered questionnaires,
interviews, use of computers) can produce different results.
Methods to reduce social desirability bias in behavioural data
• Minimize the association between the survey and intervention programmes.
• Ensure that interviewers are of the same sex as the respondent.
• Assure individuals in the programme that their responses are confidential, not shared and their answers
will not affect their access to services.
• Consider avoiding face-to-face interview methods for collecting behavioural data. Alternatives include:
• audio- or computer-assisted interviewing methods
• polling booth interviews for selected questions.
Include multiple questions on a similar topic
• Assess the consistency of responses or use composite measures of risk behaviour to assess trends.
• Ask questions that are unlikely to change as a result of the intervention programme. For example, ask
about the number of casual sex partners or condom use with regular partners.
• See if high levels of behavioural indicators have changed and are also evaluated.
When to use rapid situation assessment and when to use behavioural surveillance survey
It is not always necessary to have highly precise behavioural data. Rapid situation assessments (RSA)
may be a cost-effective alternative if you do not have enough resources to conduct formal biobehavioural
surveillance surveys. Well-implemented rapid situation assessments may provide evidence suggesting that
high-risk acts such as the use of non-sterile injections and unprotected sex happen frequently among a large
proportion of the population being characterized. More information can be found at http://www.who.int/hiv/
pub/prev_care/tgrar/en/.
If you want to use rapid situation assessment to collect risk intensity data, it is important to use standardized
methods and measures of monitoring or quality control. This will ensure that the basis of comparison is fair.
An absence of data due to a rapid situation assessment done too quickly or poorly should not be taken as
evidence for an absence of risk.
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