Prevention interventions that aim to reduce HIV transmission through behaviour change have been used since the beginning of the HIV epidemic. Employed in combination with structural and biomedical interventions, behavioural interventions continue to play an important role in HIV prevention.

This article summarizes a large systematic review of over three dozen meta-analyses of studies that evaluated the factors that impact the effectiveness of behavioural interventions to prevent sexual transmission of HIV and other sexually transmitted infections (STIs).1

What are behavioural interventions?

Behavioural interventions seek to prevent transmission by helping people change their sexual and drug-using behaviours that place them at risk for HIV. Behavioural interventions provide knowledge and skills to influence people’s motivation and capacity to enact behaviour change. They can be targeted at multiple levels: individuals, couples, families, peer groups or networks, institutions and entire communities. They can also attempt to motivate behaviour change through a range of educational, motivational, peer-group, skills-building and community approaches.

Interventions can target different behaviours like the number of sex partners a person has or the correct and consistent use of effective prevention approaches such as condoms.

What kind of research does the systematic review include?

The systematic review sought to identify the factors that increase the effectiveness of behavioural interventions to increase condom use or lower the incidence of HIV or other STIs. It focused on factors that may impact the success of interventions in three categories:

  • How the intervention was delivered
  • Who was delivering the intervention
  • Content characteristics of the intervention

The review included 37 meta-analyses. A meta-analysis combines data from multiple studies to get a better overall picture of the outcome being studied. A meta-analysis was included if it:

  • Looked at the moderating effect of at least one of the selected factors on condom use or HIV/STI infection rate
  • Was published from 2000 to 2015 in a peer-reviewed journal

A meta-analysis was excluded if it:

  • focused on pregnancy prevention interventions that didn’t also address HIV/STI prevention
  • focused on interventions that addressed HIV/STI prevention among people living with HIV, including vertical transmission, or focused on evaluating STI testing, HIV counselling and testing or HPV vaccination outcomes
  • focused on abstinence interventions that looked to reduce sexual activity rather than promote condom use/protection
  • only looked at moderating effects on sexual activity outcomes, such as number of sexual partners or frequency of sexual activity

What intervention factors did the systematic review consider?

Different interventions targeting the same outcome may contribute to a greater or smaller change in the intended outcome (known as the effect size). This may be because of different factors in the way the intervention was delivered. This review examined the factors of behavioural interventions that moderated the outcome effect size.

How the intervention was delivered

The systematic review looked at the moderating effect of six factors related to how the intervention was delivered. The factors considered were:

  • total duration of the intervention
  • number of sessions
  • school setting
  • clinic setting
  • community setting
  • group delivery

The authors concluded that none of these factors had a significant and consistent positive impact on intervention effectiveness.

Who was delivering the intervention

The systematic review examined how the person delivering an intervention can influence its effectiveness. The five factors considered were:

  • delivery by a peer (lay person sharing one or more characteristics with participants, such as gender or sexual orientation)
  • delivery by a professional (such as a healthcare provider or counsellor)
  • matching the provider and participants in ethnicity
  • matching the provider and participants in gender
  • similar age of provider and participants

The authors concluded that only matching on ethnicity and gender had a significant positive impact on intervention effectiveness, with gender matching producing the greatest number of positive effects.

Content characteristics of the intervention

The systematic review examined how the content of an intervention may impact its effectiveness. The 16 factors considered were:

  • targeting or tailoring the content to a specific group
  • tailoring the content to each individual
  • basing the content on prior formative research
  • basing the intervention on a theory of health behaviour
  • providing information on HIV/STI transmission or prevention
  • content that aims to enhance motivation for behaviour change
  • content that uses threat- or fear-based arguments or addresses perception of risk
  • content that aims to change attitudes towards risk behaviours
  • content that addresses social norms or the influence of peers
  • content that addresses barriers to condom use
  • content that addresses self-efficacy for safer sex and/or other protective behaviours
  • content that addresses behavioural strategies for reducing risk such as considerations when using drugs or alcohol
  • training on a variety of risk reduction skills or set of unspecified risk reduction skills
  • condom use skills training
  • intrapersonal skills training beyond condom use training, such as decision-making skills
  • interpersonal skills training, such as condom use negotiation

The authors concluded that the most consistent positive effects were observed for condom skills and intrapersonal skills training. Group targeting/tailoring, theory-based interventions, providing information about HIV/STI transmission or prevention methods, and use of attitudinal change arguments were also found to have positive effects.

What are the implications of the review for behavioural interventions in Canada?

This review used the results from 37 meta-analyses to examine factors that positively impact the effectiveness of behavioural interventions to increase condom use. Service providers can take these factors into consideration when developing behavioural interventions to help increase their effectiveness.

The following factors were the only ones identified as having a consistent, positive impact on intervention effectiveness:

  • intervention delivery by someone matching the gender or ethnicity of participants
  • targeting or tailoring the content to a specific group
  • basing the intervention on a theory of health behaviour
  • providing information on HIV/STI transmission or prevention
  • content that aims to change attitudes towards risk behaviours
  • condoms skills training
  • intrapersonal skills training beyond condom use training, such as decision-making skills

When considering these recommendations, it is important to remember that:

  • The review found many meta-analyses where a factor had no impact on the outcome. The authors note that this may have happened in some of these meta-analyses because of small sample sizes. This may have led to conclusions that certain factors were not important even though they may have been.
  • The date of the studies included in the 37 meta-analyses may have an impact on the moderating effects observed. Analyses based mainly on older studies may not reflect the impact that current developments and practices in HIV prevention may have on the delivery of behavioural interventions.
  • Although HIV and STI incidence effect size was examined in the review, only seven meta-analyses reported on incidence rate outcomes, which restricted the authors’ ability to draw conclusions from this effect. With further research the impact on this outcome could be explored in the future.
  • In their analysis, the authors noted any associations they observed between the outcome effects and other characteristics of the meta-analyses. For example, three of the four meta-analyses that provided positive effect sizes for skills training were focused on youth. While the authors were only able to highlight these potential associations with the data available, they could be further explored with additional research.

What is a systematic review?

Systematic reviews are important tools for informing evidence-based programming. A systematic review is a critical summary of the available evidence on a specific topic. It uses a rigorous process to identify all the studies related to a specific research question. Relevant studies can then be assessed for quality and their results summarized to identify and present key findings and limitations. If studies within a systematic review contain numerical data, this data can be combined in strategic ways to calculate pooled estimates. Combining data to produce pooled estimates can provide a better overall picture of the topic being studied.

By Erica Lee

Source: http://www.catie.ca/en/pif/fall-2017/what-factors-increase-effectiveness-behavioural-interventions-hiv-prevention?utm_source=fb&utm_medium=socmed&utm_campaign=081117&utm_content=en