Effects of Behavioral Intervention Content on HIV Prevention Outcomes: A Meta-Review of Meta-Analyses

This study is a meta-review to systematically examine which type of intervention content is more likely to lead to successful HIV outcomes. The article is from the JAIDS: Journal of Acquired Immune Deficiency Syndromes supplement addressing clinicians and public health scientists in the field of HIV prevention and treatment who might value information on health communication. (Footnotes removed by the editor.)

Problems in scientific reports that have impeded clear knowledge to explain why some communication-based interventions succeed and others fail include:

• "methodological statements describing the content of the intervention have often omitted critical detail,
• interventions commonly confound different communication element,
• descriptions of control condition communication content have been even more cursory than those of intervention,
• sample biases may be inadequately described, and,
• because of the foregoing problems, subsequent studies can only partially replicate the methods of a prior trial."

This meta-review: "offers an assessment of the state of the science on how intervention content relates to HIV risk reduction; address[es] limitations of the meta-review, make[s] recommendations for future intervention trials and for meta-analyses of these trials, comment[s] on meta-analyses focused on adherence to antiretroviral therapy (ART), and propose[s] the use of formal, comprehensive taxonomies in future HIV intervention trials and relevant meta-analyses."

The researchers chose a sample of 56 psychological, social, or behavioural HIV prevention meta-analyses from a previous meta-review. The coding of elements in these studies included looking at intervention content dimensions, efficacy, and outcomes, among others, and used the number of Google Scholar citations per year as the measure of impact. "An intervention content dimension was operationalized as a type of message or activity or a stated strategy about messages or activities undertaken in the intervention, such as providing information or facts, assessing personal risk, or teaching behavioral skills."

Judged through scholarly impact, the researchers suggest that people access meta-analyses for the purpose of asserting "that interventions have been shown to be efficacious in reducing risk for HIV in relation to some target population. Indeed, nearly all meta-analyses in this literature report statistically significant reductions in risk behavior and other relevant outcomes for those who participate in interventions as prior meta-reviews have shown." However, few studies take into account all of the intervention content (IC) factors (many look at one intervention, such as motivational interviewing). Thus, "consumers of meta-analyses should be encouraged to take advantage of moderator trends in meta-analyses, which show how effect sizes vary based on coded features, such as intervention content."

The research discusses standardisation of both future trials and meta-analyses of trials by: focusing "specifically on potential BCTs [behaviour change techniques] underlying risk behavior" and using "a shared and standardized method of classifying intervention content in the form of taxonomies of BCTs.....The principal strengths of adopting a BCT approach are its precision in stating the specific element(s) of a message in a fashion that enables greater precision in research, which in turn should translate into improved success when trials' outcomes are generalized to the community."

An example of the value of using agreed-upon BCT taxonomies is in the area of skill provision because it was shown that it helps reduce HIV risk. "Yet, BCT taxonomy research has mapped several more precise BCTs related to skills, such as behavioral rehearsal or practice, skills in self-assessment, goal setting, and self-monitoring, and social support and persuasive skills." Also, intervention content present in the control arm of most studies was rarely examined.

Avenues for methodological improvements in specifying BCTs and analysing and evaluating HIV-related interventions include:

• Both intervention design and research require training for a thorough understanding of the taxonomy to assure reliable and valid coding. An online open-access training course is available.
• "Given that behavioral interventions are often delivered with less than 50% fidelity to that explicitly defined by a treatment manual," intervention components are often confounded and poorly reported. "If researchers more often systematically and cleanly manipulated the dimensions posited to improve the targeted outcomes, evidence synthesis could proceed more efficiently.”
• "[P]recision in the reports of the content of interventions delivered is clearly necessary for a science of behavior change to advance or for implementation efforts to succeed.... Fortunately, reporting standards are improving, as shown in at least 2 efforts: (1) the Workgroup for Intervention Development and Evaluation Research (WIDER) has developed a checklist to assess the quality of the reporting of interventions in systematic reviews.... (2) the Template for Intervention Description and Replication (TIDieR) provides a checklist of the minimum information required to report interventions...."
• Standardising differences in samples of participants so as to indicate how representative they are of the communities from which they are sampled can be tied to census data. "Health-related research would benefit from a standard method to gauge key features of their samples - including both community factors and health status at a moment in time. Systematic reporting of sample characteristics could then be linked to studies of the effectiveness of BCT, enabling science to state with greater precision the effectiveness of BCTs on HIV prevention within specific populations."
• Use of larger samples in future meta-analyses by broadening selection criteria can enrich knowledge about the particular BCTs that underlie intervention success.

The research concludes by reiterating that standardisation in research on behaviour change interventions would be valuable. It recommends measures of dose-responses in relation to risk reduction. It also recommends examining whether any aspect of the social milieu surrounding risk reduction in interventions has any bearing on results. "Future meta-analyses should explore such possibilities in detail. Effective interventions targeted at populations living in challenging circumstances deserve special attention."