Presentation on theme: "5-1-1 Unit 1: Introduction to the course and to behavioural surveillance."— Presentation transcript:
5-1-1 Unit 1: Introduction to the course and to behavioural surveillance
5-1-2 Purpose and objectives To improve the capacity of countries to implement high-quality and sustainable behavioural surveillance by providing those involved with surveillance with the theory, methods and hands-on experience they need to help design and implement behavioural surveillance.
5-1-3 The course aims to enable you to: 1. Outline the use of behavioural surveillance data and the steps in developing surveillance systems 2. Select and adapt indicators, instruments and methodologies to track changes in HIV risk behaviours 3. Select and apply appropriate sampling methodologies for monitoring HIV risk behaviours 4. Ensure behavioural surveillance data is used by understanding how to analyse and present data for different audiences 5. Understand the ethical considerations involved in conducting behavioural surveillance 6. Conduct pre-surveillance activities to help develop an appropriate behavioural surveillance plan
5-1-4 Course structure Day 1 Day 2 Day 3 AM Introduction to behavioural surveillance Steps in implementing behavioural surveillance Survey methods Data analysis and use Ethical considerations in behavioural surveillance PM Measures & indicators for behavioural surveillance Sampling approaches Pre-surveillance activities
5-1-5 Introductions 1.Introduce yourself 2.Tell us a bit about your experience and your interests in behavioural surveillance 3.What are your expectations for this course?
5-1-6 Introduction to behavioural surveillance
5-1-7 After completing this unit you should be able to: Define surveillance Outline the uses of behavioural surveillance Outline issues to consider when designing a surveillance system Outline the steps required to achieve a sustainable surveillance system
5-1-8 What is surveillance? Surveillance is the systematic, regular, ongoing collection and use of data for public health action. HIV/AIDS surveillance can be divided into biological and behavioural surveillance. Behavioural surveillance involves regular and repeated cross-sectional surveys collecting data on HIV risk behaviours and other relevant issues that can be compared over time. Biological surveillance also involves regular and repeated cross-sectional surveys, but collects biological samples that are tested for HIV and other related illnesses, such as STIs and TB.
5-1-9 The uses of behavioural surveillance 1.To provide an early warning about which groups and areas infection is likely to spread in and between 2.To explain changes in HIV prevalence over time 3.To provide information for developing prevention programmes by identifying the populations and behaviours that are driving the epidemic 4.To monitor and evaluate the impact of prevention programmes 5. To reinforce the findings of biological surveillance 6.To raise the awareness of HIV among policy- makers
Note on using behavioural surveillance for evaluation: Unless questions on exposure to specific interventions are included, surveillance only provides evidence for the impact of programmes as a whole. Exposure questions should not be added if they deflect the focus of surveillance from detecting and measuring risk behaviours. Like most evaluation methods, surveillance does not provide conclusive evidence that the programme caused any observed changes in behaviour.
Issues to consider when designing a behavioural surveillance system
Issue 1: Whom to include What state of the epidemic is your country in? –Low-level: Prevalence is consistently below 5% in any high-risk group and below 1% in the general population. –Concentrated: Prevalence of HIV has surpassed 5% on a consistent basis in one or more high-risk groups, but remains below 1% in the general population. –Generalised: Prevalence of HIV has surpassed 1% in the general population.
Whom to include in surveillance for each state of the epidemic: State of the Epidemic Biological (annually if feasible) Behavioural Low-Level High-risk groupsHigh-risk groups annually, general population every 3-5 years Concentrated High-risk groups, general population High-risk groups annually, general population every 3-5 years Generalised High-risk groups, general population High-risk groups annually, general population annually
Why survey risk groups in a generalised epidemic if everyone is at high risk? Even in a generalised epidemic, not everyone is at equal risk of developing HIV or has an equal role in the spread or maintenance of the epidemic. It is important to identify and monitor sub- populations who help drive the epidemic.
Why survey the general population in a concentrated epidemic if they are low-risk? General population surveillance helps us understand the potential for HIV to spread beyond the groups in which it is concentrated by allowing us to explore: –The size of the risk groups –The links between the risk groups and the general population –The level of risk behaviour in the general population
Thinking beyond the guidelines Although these general guidelines are very useful when deciding whom to include in surveillance, they have limitations. Question: Look at the following map. What do you see in terms of the classification of the epidemic?
Patterns of HIV Epidemics in the World, 2001 State of the epidemic Generalised : > 1% HIV prevalence among pregnant women Concentrated: > 5% HIV prevalence among high risk groups, but < 1% among pregnant women Low Level: < 1% HIV prevalence among high risk groups No Data
Issue 2: Where to access the surveillance population The populations included in surveillance can be accessed either in sentinel site or in the community. Question: What do we mean by sentinel and community-based surveillance?
Issue 2: Where to access the surveillance population, cont. Sentinel surveillance is often more convenient, cheaper and has fewer ethical implications than community-based surveillance. People at sentinel sites are self-selected, so we do not know whom they represent or how the population changes over time. When community-based surveillance uses rigorous sampling techniques, the people whom the sample represent can be clearly defined.
Issue 3: How to link behavioural and biological data Behavioural data are important for interpreting biological data over time. To ensure data are complementary and useful, biological and behavioral surveillance are best planned together. Planning should include how the data can best be linked.
What do we mean by linking? Collecting HIV, STI and behavioural data from the same individuals at the same time. Collecting HIV, STI and behavioural data from the same source population at different times. Analyzing HIV, STI and behavioural data from a similar source population, using whatever data are available. Reporting behavioural and biological surveillance together. The decision about how data should be linked should be country-specific. Whatever type of linking is used, remember it is only possible to link trends over time. Data from a single point in time cannot be linked.
Issue 4: How to ensure that surveillance is appropriate for the context There are broad guidelines on how to do surveillance for different stages of the epidemic. However, there is no one size fits all way of designing a surveillance system. The surveillance system needs to be designed to fit the specific features of each countrys epidemic. The things that we discuss in this training are not rules everything will need modifying to fit the countrys needs.
An overview of the steps for conducting surveillance
Step 1: Identify a co-ordinating body Purpose: to provide guidance and serve as an over- all decision-making committee for the surveillance system, to ensure that the surveillance system collects appropriate data that allows trends to be measured and to inform policy. The committee should be convened by the ministry of health, and should include national and international bodies whose interests are served by surveillance.
Step 1, continued Responsibilities of the committee: – To define the purpose of surveillance – To ensure that surveillance is set up to meet the countrys data needs – To identify funding sources – To advocate about the importance of surveillance – To facilitate co-ordination between surveillance partners – To make final decisions about surveillance populations and areas – To monitor the progress of the surveillance process – To provide input into data interpretation and conclusions – To maximise data dissemination and use
Step 2: Agree on the purpose of surveillance Purpose: to ensure that stakeholders have similar ideas about the purpose and practicalities of surveillance. Step 3: Establishing criteria for selecting populations and geographic coverage areas Purpose: to ensure that surveillance populations and geographical areas are selected based on their epidemiological importance.
Step 4: Gather information to select populations & geographic areas and to guide survey implementation Purpose: to collate and collect data required to select populations and geographical areas. 1. Review previous research to assess what is currently known about the epidemic 2. List potential surveillance populations and geographic hot spots 3. Conduct field assessments as needed
Step 5: Finalise selection of sub- populations & geographic areas for surveillance Purpose: to ensure that the information reviewed and collected is synthesised and used by the surveillance committee. Step 6: Develop sampling design Purpose: to ensure a sampling design that is appropriate for the surveillance population and results in the collection of unbiased and precise estimates.
Step 7: Develop survey protocol ( See table 1.4 for suggested content ) Purpose: to ensure that all surveillance elements are considered and planned for and to ensure that procedures are documented, so the system uses consistent methodologies over time.
Step 8: Build sampling frame Purpose: to generate a list of units from which the sample can be selected if required. Step 9: Conduct surveillance Purpose: to carry out the surveillance protocol.
Step 10: Analyse and use data Purpose: to analyse data appropriately and present/disseminate it in a manner that facilitates its use. Step 11: Plan for next round of surveillance
Small group discussion 1.How is surveillance organised/co-ordinated in your setting? What works and doesnt work in the organisational structure? 2.Look at the diagram on the next slide. This diagram was developed using behavioural surveillance data from the areas in Asia where the majority of epidemics are concentrated. The diagram helps us understand what behaviours are driving the HIV epidemic, the size of high-risk groups and their links to the general population. The ovals show the different population groups and their sizes; the arrows show the links between the populations and the strength of the links. Describe how you could use the information shown in the diagram in your country.
Data from behavioural surveillance in Asia Low or no-risk females Clients of FSW: 5-20% of population Low or no-risk males MSM: 2-3% of population IDUs: 0.1-5% of population FSW: 0.3-1% of population Source: Tim Brown, East West Center
Case Study When discussing guidelines for whom to include in surveillance for each epidemic state, what do we mean by the general population and by high-risk group surveillance? Are commercial sex workers a high-risk group?
Key references: FHI et al (2000). Behavioral surveillance surveys: Guidelines for repeated behavioral surveys in populations at risk of HIV. Arlington, FHI. FHI et al (in press). The pre-surveillance process: Guidelines for planning HIV surveillance systems UNAIDS (2002). Initiating second generation HIV surveillance systems: practical guidelines. WHO & UNAIDS: Geneva, WHO (2001). Guidelines for conducting HIV behavioral surveillance. WHO, SEA-AIDS- 123: New Delhi.