Behavioral Surveillance Lessons Learned in the Western Pacific Region

1
Behavioral Surveillance Lessons Learned in the
Western Pacific Region

• Malaysia, January 2003
• Dr. Nguyen Thi Thanh Thuy, HSI Focus/WPRO

2
Behavioral Surveillance Surveys (BSS) in the WPR

• BSS repeated surveys in design, to monitor
  behavioral trends
• Phillipines from 1997
• Laos one round (2001)
• Vietnam two rounds (2000-2002)
• Mongolia one round 2002
• One time cross-sectional surveys Project-based
  or research based surveys
• Many countries

3
BSS

• Repeated cross sectional surveys
• Quantitative surveys

4
Objectives of the surveillance

• To diagnose at-risk groups one round
• To help to explain HIV prevalence trends
• populations comparable sharing sampling frames
  for HSS and BSS
• To evaluate interventions (methodological rigor)

5
Role of BSS rounds

• The first round is sometimes a pilot round,
  not used as baseline for monitoring trends
• Some groups may not be continued (no risk
  found, no intervention)
• Methodologies would be improved for the next
  round (with some changes), not consistent
• Repeated rounds may not be advisable unless there
  are ongoing interventions

6
Selecting sub-populations (1)

• Depending on the epidemic state
• Low level Epidemic
• Groups at high risk Hard-to reach groups (e.g.
  SW, IDU, MSM, mobile populations)
• Concentrated Epidemic
• High risk groups, and bridging groups (e.g.
  clients of
• SW truck drivers, police, military)
• Generalized epidemic
• General population Accessible groups (married
  women, students)
• Difficult to define groups

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Selecting sub-populations (2)

• Conduct an assessment covering potential groups
  and locations, to verify that a large enough
  volume exists to warrant a quantitative survey,
  and that access to the groups members is
  feasible.
• Do assessment prior to mapping for BSS

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The critical points of the assessment phase

• Choosing the right groups
• Ethnographic, epidemiological, political
• Accessing the right groups
• Focusing on key risks
• Not harming already marginalised groups
• Establishing feasibility

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Indicators

• How many is enough (depending on objective)
• Considering standardized and relevant indicators
• Questionnaire not too long
• What are key indicators?

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Validity of the Data

• Lying about risk behavior or misunderstanding the
  questions?
• Field test of questionnaires, well-trained
  interviewers can help reduce these problems
• Qualitative research can assist in clarifying
  unexpected or confusing quantitative findings

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Role of qualitative studies

• Qualitative methods (e.g. in-depth interview,
  focus group discussion) can explain why trends
  change and confirm/ complement quantitative
  trends
• Draw samples and case studies from the formative
  research can be conducted

12
Sample size and sampling

• Sample sizes depend on objectives of the survey.
  (e.g. for evaluation, the sample must be large
  enough to measure changes)
• Probability sampling methods (more
  representative) are more solid for monitoring
  trends
• Available resources should be considered

13
Mapping

• Identifiation of locations of surveyed subjects
  and N.
• of subjects per location
• Comprehensive maps are the key to effective
  sampling (for both random and convenience
  sampling)
• Access to hidden and marginalized populations
  such as SW, IDU
• protect the privacy and safety of interviewers
  and interviewees

14
Use of data

• Policy/advocacy and program planning
• Currently neither is done efficiently
• Weakness of using behavioral data and biological
  data to fully describe epidemics
• Lack of use BSS data as tools for monitoring and
  evaluation of National programs on HIV/AIDS