FHI - Recommended Mix

6. Recommended mix of data collection methods

As is now clear, different data collection methods deliver different products with varying levels of cost and complexity. To use its resources most efficiently, a national programme must make choices about what mix of methods to adopt, with what frequency, and on what scale. These choices will reflect the stage of the epidemic in a country as well as the political and social environment, the existing capacity for research, and available resources.

Family Health International, UNAIDS, and their partner organisations have made recommendations for a minimum package of behavioural data collection for each major stage of the epidemic. These recommendations are part of the UNAIDS/WHO guidelines for second generation surveillance systems and are based on the assumption that HIV serosurveillance is in place or is being developed in line with those guidelines.

Obviously, many countries will already have put in place some or all of the data collection mechanisms recommended. Tables 4 to 6, which summarise the minimum package for each stage of the epidemic, can serve as a checklist for countries planning to strengthen their behavioural data collection efforts.

6.1 Stages of the HIV epidemic

The HIV epidemic has developed differently in different parts of the world. It was originally categorised by major transmission modes into "Pattern One" countries, where the virus was concentrated mostly in homosexual male and drug injecting communities, and "Pattern Two" countries, where HIV spread mostly between men and women during sexual intercourse. Recent shifts in patterns of infection in some countries now suggest another classification that allows for the movement of countries or regions between categories. UNAIDS and its partners have developed a classification that groups HIV epidemics into three types: low-level, concentrated, and generalised (Table 3). Countries will have different information needs in each epidemic stage, and these needs may shift if the epidemic develops and moves from one type to another.

Table 3. Stages of HIV Epidemics

Type	Defining Characteristics
Low-level	HIV prevalence has not exceeded five percent in any defined group.
Concentrated	HIV infection continues to be concentrated in highly vulnerable groups and has been recorded at over five percent prevalence in at least one of those groups. In pregnant women, however, prevalence is below one percent.
Generalised	HIV prevalence is higher than one percent in pregnant women.

Low-level epidemics are epidemics with an HIV prevalence assumed to be less than five percent in all known subpopulations presumed to practice higher-risk behaviours. Countries in the low-level stage of the epidemic might initially focus their surveillance efforts on populations with higher levels of HIV-transmitting behaviours, such as sex workers, truckers, migrant workers, military personnel, men who have sex with men, and drug injectors. The aim will be to monitor the trends and levels of infection within these groups and also to map the dynamics of infection and sexual mixing patterns that are construed as high-risk or low-risk in nature.

Concentrated epidemics are epidemics with an HIV prevalence that has surpassed five percent in one or more subpopulations presumed to practice higher-risk behaviours but remains less than one percent among pregnant women.

Generalised epidemics are epidemics in which HIV has spread far beyond the subpopulations with higher-risk behaviours, which are now heavily infected. Prevalence among pregnant women is above one percent. In such epidemics infection levels in rural population may be fast mirroring those in urban areas. Most countries in sub-Saharan Africa have an established epidemic that goes beyond just populations practising high-risk behaviours. The generalised nature of the epidemic in this region calls for surveillance systems that give a cross-sectional profile of the infection in the general population.

6.2 Behavioural data collection in a low-level epidemic

In low-level epidemics, the risk of HIV infection is likely to be concentrated among those with higher levels of risk behaviour in a country. Depending on the country, these might include sex workers and their clients, drug injectors, men who have sex with men, or other populations. In this type of epidemic, it is recommended that HIV prevalence studies also focus on those with higher-risk behaviours. Risk behaviour may exist in the general population, however, and the links between higher- and-lower risk populations need to be investigated.

Many countries with low-level epidemics have not felt the need to invest resources in collecting behavioural data, assuming that if the virus is largely absent, risk behaviour must be limited. However, it is exactly at this point of the epidemic that behavioural data can act most effectively as a warning system. Where behavioural data and other indicators such as STD or hepatitis B prevalence show that people are having unprotected sex with multiple partners or are sharing injecting equipment, it may simply be a matter of time before HIV follows.

Collecting information on behaviour at this stage spotlights potential flash points for HIV infection. It can raise awareness among the public and among policymakers of the dangers posed by not doing anything to keep the virus confined at low levels, and it can help suggest what must be done, and for whom.

Preliminary assessment: identifying risk behaviours
This first step in the preliminary assessment might be described as the "homework" stage of data collection. It provides a preliminary picture of what is already known about risk behaviour in a country. This involves gathering all existing studies, published and unpublished, trawling through press reports and other sources of anecdotal information, and speaking to people likely to have information on sexual and drug-taking behaviour. In most countries, such research will provide enough information to identify the behaviours more likely to spread HIV and to characterise the individuals or groups that are more likely to engage in those behaviours. There are very few countries where all high-risk behaviours are equally represented; therefore, behavioural data collection should focus on those more likely to be driving the epidemic in a given country.

In many countries this information on risk behaviour will already be available as part of the analysis of epidemiological data on HIV/AIDS reporting or of a situation assessment carried out as part of a strategic planning exercise. Occasionally, this review will point to gaps in existing information about the epidemic that must be filled with basic anthropological research. Where no information exists and risk behaviours must be identified from scratch, the research may take up to three months.

Preliminary assessment: quantifying populations with higher risk
Behavioural data collection in a low-level epidemic will focus on populations with higher levels of risk behaviour. These populations must be quantified if representative data are to be collected. This generally involves a mapping of sites where the behaviours take place, such as brothels, shooting galleries, gay bars, and cruising areas, together with an estimate of the number of individuals associated with each site.

Preliminary assessment: examining links with the general population
The data needed to plan effective HIV prevention programmes in a low-level epidemic will depend on how much individuals and communities with higher levels of risk interact with those with lower risk. Qualitative research -- in-depth and key informant interviewing and perhaps focus group discussions -- among people with higher risk can help identify interactions with the general population. In using the term "general population" we recognise that it is a composite of many subpopulations and that people at higher risk are part of the overall general population. Accordingly, where these links are widespread, the behavioural data collection system must include general population surveys. This is most often the case where commercial sex is common, but the need may also arise where men frequently have sex with both men and women or where drug injectors are sexually active with people who do not use drugs.

Qualitative research can be as costly and time-consuming as a quantitative survey. Sample sizes are therefore small, and results may not be representative of the total source population. However, this type of research provides essential input for the design of survey questionnaires that will yield relevant, informative, and actionable data from a larger population sample. It may also provide information that will inform the sampling process. Therefore, qualitative research is an essential requirement for the design of appropriate prevention programmes.

Behavioural monitoring: populations with higher-risk behaviours
Once the populations with higher levels of risk behaviour have been identified and quantified, behaviour can be surveyed and risk quantified. Using random probability sampling or other sampling methods and a sampling frame constructed during the mapping process, a behavioural survey provides information that is representative or close to representative for the group in question. It acts as a baseline and can be repeated using identical sampling methods to measure change over time. The sample size will vary depending upon the population size and the frequency of the behaviours to be measured. Generally, sample sizes will fall between 250 and 400 respondents.

It is assumed that the data provided by baseline surveys will be used to design and promote programmes that aim to reduce risk behaviour. The frequency of subsequent survey rounds is recommended to be at least every other year but will at this stage depend on the nature of the programmes intended to benefit the survey population. The first round of data collection will always be the most costly and time consuming, as it involves training and concentrated work on a sampling frame. Collecting and analyzing the data for single round of a behavioural survey in selected population groups may take between three and six months, depending on the number of target populations and survey areas.

Some groups with higher levels of risk behaviour may be impossible to sample in a systematic and replicable way, or in numbers great enough to provide significant results. For these groups, ad hoc surveys linked to prevention programmes are recommended. Programmes aimed at changing behaviour in such groups should in any case have a component built in to monitor change over time; these evaluation techniques can be a useful addition to a broader behavioural data collection system.

Data on HIV prevalence in these groups should be collected on a voluntary basis with informed consent as part of service provision.

Behavioural monitoring: general population
The qualitative research will reveal links between populations with higher levels of risk behaviour and the general population. If they appear widespread, then a household-based survey of the general population is needed to determine what proportion of the population is at risk of acquiring HIV infection through contact with subpopulations more likely to be infected.

It is worth noting that this contact may shift over time in response to the epidemic itself. General population data may therefore provoke a revision of groups included in targeted survey systems. For example, men in general population surveys in Thailand reported a reduction in brothel-based sex but an increase in commercial sex with hostesses in restaurants and bars. Such a shift may require a remapping of the populations with higher levels of risk behaviour and construction of a new sampling frame for targeted behavioural surveys.

Household-based population surveys are a great asset in building support for HIV prevention activities among policymakers and the general public, especially when they demonstrate that behaviour has changed following past prevention efforts. It is therefore recommended that, where there are clear links between the general population and those with higher-risk behaviour, general population surveys be carried out every four to five years. It may be possible to reduce the cost of these surveys drastically by adding appropriate questions on sexual behaviour to existing household survey rounds, but the particular sensitivities of the topic must be considered. For example, interviewers in general health survey rounds may need extra training before asking questions about sexual behaviour.

Table 4: Behavioural Data Needs and Methods in a Low-Level Epidemic

Data Needs	Method	Questions Answered	Frequency	Duration*
Preliminary assessment	Review existing data	What is already known? What are the gaps in current knowledge?	One time
	Rapid assessment of risk behaviours	Which high-risk behaviours are driving the epidemic in this country?	One time	3 months
	Mapping of at-risk populations	Where do people engage in risk behaviour? How many people are associated with each site?	One time	1 month
	Qualitative research	What particular behaviours must change? Is there resistance to change? What are links with general population? What type of intervention is most appropriate?	One time	2 months
Behavioural monitoring	Repeated surveys in populations with high-risk behaviour	How widespread is risk in defined high-risk-behaviour groups? How widespread are safer behaviours? How common are links with general population? How has behaviour changed over time? And since before the intervention?	Annually/ biannually	3-6 months
Behavioural monitoring	Where qualitative research points to links between high- and low-risk groups: Repeated surveys in the general population	What proportion of the general population is a sexual partner of someone with high-risk behaviour? Which behaviours put them at risk?	Every 4-5 years	6-9 months

*Duration: includes all research or survey stages from preparatory work to the production of findings.

6.3 Behavioural data collection in a concentrated epidemic

In a concentrated epidemic, the virus may remain confined to circles of people with higher-risk behaviour because there are few links between those populations and the general population. It may remain concentrated because there is very little risk behaviour in the general population. Or links and generalised risk behaviour may exist, but HIV may not have infected enough individuals to result in explosive growth. In that case, it may be just a matter of time before the epidemic becomes generalised. Determining which of these situations is the case and designing and measuring the success of the appropriate interventions are the key purposes of behavioural data collection in a concentrated epidemic.

At the concentrated stage of the epidemic, it is recommended that countries continue serosurveillance among the groups in which infection is concentrated and begin monitoring HIV in the general population, especially in young people. Behavioural data collection will increase the usefulness of this serological data.

Preliminary assessment in populations with higher risk
Because concentrated epidemics affect more people and present a greater risk to a country than low-level epidemics, there is an even greater likelihood that the data required for preliminary assessment of risk behaviour in the country will already be available. If it is not, the same steps outlined for countries with low-level epidemics should be followed.

Behavioural monitoring: populations with higher-risk behaviours
In a low-level epidemic, the frequency of behavioural surveys in populations with higher-risk behaviours will depend on the prevention activities carried out in that community (and may be guided by changes observed in serosurveillance). In a concentrated epidemic, by contrast, behavioural data should be collected much more systematically. Surveys in selected population groups with higher-risk behaviour should be designed to collect representative data annually or biannually, depending on available resources.

The qualitative research performed in the preliminary assessment stage may identify definable groups that overlap extensively with both the general population and populations with higher-risk behaviours. If so, programme planners may consider adding these groups to those included in the targeted behavioural survey system.

Table 5. Behavioural Data Needs and Methods in Concentrated Epidemic

Data Needs	Method	Questions Answered	Frequency	Duration*
Preliminary assessment (if not yet done or if it needs to be broadened geographically or in other groups )	Review existing data	What is already known? What are the gaps in current knowledge?	One time
	Rapid assessment of risk behaviours	Which high-risk behaviours are driving the epidemic in this country?	One time	3 months
	Mapping of at risk populations	Where do people engage in risk behaviour? How many people are associated with each site?	Repeated if survey data shows population or behavioural shift	1 month
	Qualitative research	What particular behaviours must change? Is there resistance to change? What are links with general population?	One time	2 months
Behavioural monitoring and	Repeated surveys in populations with high-risk behaviour	How widespread is risk in high-risk-behaviour groups? How common are links with the general population? How do these behaviours change over time?	Annually /biannually	3-6 months
Explaining trends in HIV prevalence	Repeated surveys in the general population Sampling with emphasis on geographical areas with key HIV sentinel sites	What proportion of the general population has sex with someone with risk behaviour? Which behaviours put them at risk?	Every 4-5 years	6-9 months
Explaining trends in HIV prevalence	Repeated surveys in young people Sampling with emphasis on geographical areas with key HIV sentinel sites	What are the risk behaviours among young people? At what age do they begin? How do they change over time? Do trends in self-reported risk behaviour correlate with observed changes in HIV prevalence (e.g., explaining transition to generalised epidemic)?	Every 2-3 years	3-6 months

*Duration: Includes all research or survey stages from preparatory work to the production of findings.

Behavioural monitoring: general population
General population surveys are recommended in all concentrated epidemics. As in low-grade epidemics, they should aim to identify what proportion of the population has sex with members of identified groups with higher-risk behaviour and which risk behaviours are most likely to lead to HIV.

In concentrated epidemics, household-based surveys can help explain increases in HIV prevalence seen in sentinel serosurveillance. Designers of these surveys should bear in mind the location and population served by sentinel sites and should sample in geographical areas with key HIV sentinel sites. In order to monitor trends over time, it is recommended that general population surveys be repeated every four to five years.

Behavioural monitoring: young people
Young people are particularly vulnerable and are the key to the future course of the HIV epidemic. They are an essential focus for prevention messages in every sexual health programme. Since most new infections are in young people, modest changes in behaviour in this age group may have a significant impact on the epidemic. It is recommended that their knowledge, attitudes, and sexual behaviour be monitored once there is a concentrated epidemic.

In general, it is recommended that young people's behaviour be studied in household-based surveys, supplemented by surveys in particular groups of young people (homeless youth, young drug injectors) who may not be found in a typical household survey.

The exact age groupings will vary according to the local situation. In countries where the mean age at first sex is in the early 20s, resources should be concentrated in the 20- to 24-year-old-group. Countries where a large proportion of the population is sexually active by age 15 may consider including 12- or 13-year-olds. A rise in age of sexual inception is an important response to HIV prevention messages, so it may be necessary to track behaviour in both teenagers and people in their early 20s. It is recommended that surveys be repeated in these groups every two to three years, with sample sizes between 400 and 500 in each age and sex group (males and females younger than 20, and 20 to 24 years).

6.4 Behavioural data collection in a generalised epidemic

Groups with particularly high levels of risk behaviour may continued to drive new infections in a generalised epidemic, but the pattern of HIV spread goes far beyond higher-risk individuals and their immediate partners. By the time an epidemic becomes generalised, it is usually clear what the major risk behaviours are. Systematic and repeated behavioural data collection in the general population is essential for explaining changes in prevalence and tracking changes in behaviour over time. It must also focus on identifying the risk behaviours that have been neglected or have failed to respond to prevention efforts. New qualitative research may choose to explore the social, economic, and cultural context that determines who continues to be vulnerable to HIV infection and why.

Behavioural monitoring: populations with higher-risk behaviors
While it is important in a generalised epidemic to expand prevention efforts to those with somewhat lower risk of transmitting the virus, national programmes should not lose sight of groups that are driving the epidemic. Population groups practising high levels of risk behaviour still have a great impact on the spread of HIV infection in generalised epidemics. That is why it is essential to maintain a focus on interventions with those groups, and, as a logical consequence, to monitor their behavioural trends.

In every generalised epidemic to date, the overwhelming risk factor for HIV infection has been unprotected sex with a partner of the opposite sex. While other groups, such as drug injectors or men who have sex with men, may also be at elevated risk, they have not historically contributed greatly to generalised epidemics. In this context, it is recommended that surveys concentrate their resources on tracking the behaviour of sex workers and any subgroups of the general population (for example, seasonal migrant workers) that interact extensively with sex workers but that may be missed in household surveys. Targeted surveys in these groups should be carried out every year or every other year, depending on available resources.

Behavioural monitoring: general population
Regular surveys of behaviour in the general population are critical in explaining the progress of HIV infection at the generalised stage of the epidemic. They are also a suitable tool for judging the overall success of the national response in supporting the adoption of safer behaviours. Because behaviours at the general population level tend to change more slowly, it is recommended that these surveys be carried out every four to five years.

Sampling for the general population survey should be coordinated with the key sites in the sentinel HIV serosurveillance system. This will make it possible to analyse behavioural trend data in conjunction with HIV prevalence data in antenatal clinic attenders from the same catchment area. Analysis of these data by age group (if possible by single year of age in the younger age groups) will enable evaluators to make a better- informed interpretation of changes in HIV prevalence.

Because general population data are important to understanding a generalised epidemic, it is recommended that (in some instances where it might be feasible) household surveys collect data on HIV serostatus as well as behaviour. Saliva or blood specimens may be collected in households when interviews are conducted or separately in ad hoc clinics in association with clinical examination and treatment for specific diseases, including STDs. Informed consent and pre- and post-test counseling are prerequisites for this type of survey. Ethical guidance ensuring confidentiality and informed consent is needed.

Table 6. Behavioural Data Needs and Methods in a Generalised Epidemic

Data Needs	Method	Questions Answered	Frequency	Frequency Duration*
Preparation for behavioural surveys in selected population groups	Mapping of at-risk populations	Where do people engage in risk behaviour? How many people are associated with each site?	Repeated if indications of behavioural shift	1 month
Behavioural monitoring	Repeated surveys in populations with high-risk behaviour with emphasis on sex workers and their clients	How widespread is risk in high-risk-behaviour groups? How common are links with the general population? How do these behaviours change over time?	Annually/ biannually	3-6 months
	Repeated surveys in the general population	What puts people in the general population at risk of HIV infection? Has risk behaviour changed over time? Which behaviours have not changed?	Every 4-5 years	6-9 months
	Repeated surveys in young people	What are the risk behaviours among young people? At what age do they occur? How do they change over time?	Every 2-3 years	3-6 months
Explaining trends in HIV prevalence	Sampling geographical areas with key sentinel serosurveillance sites, with wide geographic /ethnic range	e.g., Are observed declines in HIV prevalence a result of behaviour change?	Linked to household-based surveys
Explaining trends in HIV prevalence	In selected sites, household surveys with data on HIV serostatus	Serological confirmation of self-reported trends in risk behaviour by age group and sex.
Contextual analysis, explaining continuing risk behaviour at community level	A range of methods, largely qualitative	What are the social, economic, or cultural factors supporting risk behaviour? How might these be changed to make sex safer? How can communities contribute to altering these determinants?	One time. Selected communities

*Duration: includes all research or survey stages from preparatory work to the production of findings.

Behavioural monitoring: young people
In generalised epidemics, the importance of behavioural patterns adopted in youth is greater than ever in determining the course of the HIV epidemic. As an epidemic matures and prevalence rises, most people exposed to HIV through their own or a partner's risk behaviour will already be infected. New infections are therefore concentrated in young people who have only recently become sexually active.

The positive side of this equation is that young people are more likely to adopt safe behaviour from the start of their sexual lives than are older people with already entrenched habits. In some countries, the only groups reporting substantial changes in behaviour in response to the epidemic are young people. And in those countries, youth are also the group in which HIV prevalence is falling most markedly.

In general, young people's behaviour should be studied in a household-based survey, supplemented by surveys in those (homeless youth, young drug injectors) who are less likely to be reached in a household survey. These young people often are at elevated risk compared to those living in household settings.

Surveys in young people should be repeated every two to three years, with sample sizes between 400 and 500 in each age and sex group (males and females younger than 20, and 20 to 24 years of age).