Using Incentives and Nudging to Improve Non-Targeted HIV Testing in Ecuador: A Randomized Trial

Impact of voluntary testing on infectious disease epidemiology: A game theoretic approach

The World Health Organization recommends test-and-treat interventions to curb and even eliminate epidemics of HIV, viral hepatitis, and sexually transmitted infections (e.g., chlamydia, gonorrhea, syphilis and trichomoniasis). Epidemic models show these goals are achievable, provided the participation of individuals in test-and-treat interventions is sufficiently high. We combine epidemic models and game theoretic models to describe individual's decisions to get tested for infectious diseases within certain epidemiological contexts, and, implicitly, their voluntary participation to test-and-treat interventions. We develop three hybrid models, to discuss interventions against HIV, HCV, and sexually transmitted infections, and the potential behavioral response from the target population. Our findings are similar across diseases. Particularly, individuals use three distinct behavioral patterns relative to testing, based on their perceived costs for testing, besides the payoff for discovering their disease status. Firstly, if the cost of testing is too high, then individuals refrain from voluntary testing and get tested only if they are symptomatic. Secondly, if the cost is moderate, some individuals will test voluntarily, starting treatment if needed. Hence, the spread of the disease declines and the disease epidemiology is mitigated. Thirdly, the most beneficial testing behavior takes place as individuals perceive a per-test payoff that surpasses a certain threshold, every time they get tested. Consequently, individuals achieve high voluntary testing rates, which may result in the elimination of the epidemic, albeit on temporary basis. Trials and studies have attained different levels of participation and testing rates. To increase testing rates, they should provide each eligible individual with a payoff, above a given threshold, each time the individual tests voluntarily.

Effectiveness of Behavioural Economics Informed Interventions for the Prevention, Screening, and Antiretroviral Treatment of HIV Infection: A Systematic Review of Randomized Controlled Trials

Failure to meet international targets set for the human immunodeficiency virus HIV pandemic suggests that more effective public health strategies are needed. New strategies informed by behavioural economics are now increasingly being tested, with promising results. However, the evidence base is diverse and challenging for policymakers to interpret. This paper aims to synthesise existing evidence by reporting results from a systematic review of behavioural economics-based interventions for addressing HIV prevention, testing and treatment. The reported study was a systematic review of randomized controlled trials. The search was conducted in four electronic medical literature databases, six trial registries, four grey literature sources and was not restricted to any country or region. Bias was assessed using criteria outlined in the Cochrane Handbook for Systematic Reviews; quality of evidence was assessed using GRADE methodology. Fifteen full text articles were included in the final analysis. The synthesis of these studies revealed that strategies involving opt-out defaults, active-choice defaults, and lottery incentives can potentially increase uptake of HIV testing. Lottery incentives also showed signs of effectiveness in improving HIV prevention, ART adherence and initiation. Despite the promising findings, the overall evidence was judged to be of moderate to very low quality. Behavioural economics-based interventions are promising behavioural change strategies, although more well-designed studies are needed to strengthen the evidence base.

Demand creation for HIV testing services: A systematic review and meta-analysis

BACKGROUND

HIV testing services (HTS) are the first steps in reaching the UNAIDS 95-95-95 goals to achieve and maintain low HIV incidence. Evaluating the effectiveness of different demand creation interventions to increase uptake of efficient and effective HTS is useful to prioritize limited programmatic resources. This review was undertaken to inform World Health Organization (WHO) 2019 HIV testing guidelines and assessed the research question, "Which demand creation strategies are effective for enhancing uptake of HTS?" focused on populations globally.

METHODS AND FINDINGS

The following electronic databases were searched through September 28, 2021: PubMed, PsycInfo, Cochrane CENTRAL, CINAHL Complete, Web of Science Core Collection, EMBASE, and Global Health Database; we searched IAS and AIDS conferences. We systematically searched for randomized controlled trials (RCTs) that compared any demand creation intervention (incentives, mobilization, counseling, tailoring, and digital interventions) to either a control or other demand creation intervention and reported HTS uptake. We pooled trials to evaluate categories of demand creation interventions using random-effects models for meta-analysis and assessed study quality with Cochrane's risk of bias 1 tool. This study was funded by the WHO and registered in Prospero with ID CRD42022296947. We screened 10,583 records and 507 conference abstracts, reviewed 952 full texts, and included 124 RCTs for data extraction. The majority of studies were from the African (N = 53) and Americas (N = 54) regions. We found that mobilization (relative risk [RR]: 2.01, 95% confidence interval [CI]: [1.30, 3.09], p < 0.05; risk difference [RD]: 0.29, 95% CI [0.16, 0.43], p < 0.05, N = 4 RCTs), couple-oriented counseling (RR: 1.98, 95% CI [1.02, 3.86], p < 0.05; RD: 0.12, 95% CI [0.03, 0.21], p < 0.05, N = 4 RCTs), peer-led interventions (RR: 1.57, 95% CI [1.15, 2.15], p < 0.05; RD: 0.18, 95% CI [0.06, 0.31], p < 0.05, N = 10 RCTs), motivation-oriented counseling (RR: 1.53, 95% CI [1.07, 2.20], p < 0.05; RD: 0.17, 95% CI [0.00, 0.34], p < 0.05, N = 4 RCTs), short message service (SMS) (RR: 1.53, 95% CI [1.09, 2.16], p < 0.05; RD: 0.11, 95% CI [0.03, 0.19], p < 0.05, N = 5 RCTs), and conditional fixed value incentives (RR: 1.52, 95% CI [1.21, 1.91], p < 0.05; RD: 0.15, 95% CI [0.07, 0.22], p < 0.05, N = 11 RCTs) all significantly and importantly (≥50% relative increase) increased HTS uptake and had medium risk of bias. Lottery-based incentives and audio-based interventions less importantly (25% to 49% increase) but not significantly increased HTS uptake (medium risk of bias). Personal invitation letters and personalized message content significantly but not importantly (<25% increase) increased HTS uptake (medium risk of bias). Reduced duration counseling had comparable performance to standard duration counseling (low risk of bias) and video-based interventions were comparable or better than in-person counseling (medium risk of bias). Heterogeneity of effect among pooled studies was high. This study was limited in that we restricted to randomized trials, which may be systematically less readily available for key populations; additionally, we compare only pooled estimates for interventions with multiple studies rather than single study estimates, and there was evidence of publication bias for several interventions.

CONCLUSIONS

Mobilization, couple- and motivation-oriented counseling, peer-led interventions, conditional fixed value incentives, and SMS are high-impact demand creation interventions and should be prioritized for programmatic consideration. Reduced duration counseling and video-based interventions are an efficient and effective alternative to address staffing shortages. Investment in demand creation activities should prioritize those with undiagnosed HIV or ongoing HIV exposure. Selection of demand creation interventions must consider risks and benefits, context-specific factors, feasibility and sustainability, country ownership, and universal health coverage across disease areas.

Applying Behavioural Insights to HIV Prevention and Management: a Scoping Review

PURPOSE OF REVIEW

This scoping review summarises the literature on HIV prevention and management interventions utilizing behavioural economic principles encapsulated in the MINDSPACE framework.

RECENT FINDINGS

MINDSPACE is an acronym developed by the UK's behavioural insights team to summarise nine key influences on human behaviour: Messenger, Incentives, Norms, Default, Salience, Priming, Affect, Commitment, and Ego. These effects have been used in various settings to design interventions that encourage positive behaviours. Currently, over 200 institutionalised behavioural insight teams exist internationally, which may draw upon the MINDSPACE framework to inform policy and improve public services. To date, it is not clear how behavioural insights have been applied to HIV prevention and management interventions. After screening 899 studies for eligibility, 124 were included in the final review. We identified examples of interventions that utilised all the MINDSPACE effects in a variety of settings and among various populations. Studies from high-income countries were most common (n = 54) and incentives were the most frequently applied effect (n = 100). The MINDSPACE framework is a useful tool to consider how behavioural science principles can be applied in future HIV prevention and management interventions. Creating nudges to enhance the design of HIV prevention and management interventions can help people make better choices as we strive to end the HIV/AIDS pandemic by 2030.

Financial Incentives, Not Behavioral Nudges, Led to Optimized HIV Testing among Pregnant Women in a High-Burden Urban Population in Ecuador

Behavioral economic principles are increasingly being used in the fight against HIV, including improving voluntary testing in sub-Saharan Africa and South America. However, behavioral nudges have not been widely tested as a strategy to optimize HIV testing in pregnant women. Here, we assessed whether behavioral nudges or financial incentives were effective in optimizing HIV testing among pregnant women in a high-HIV burden setting. A randomized clinical trial was conducted between May 21 and Oct 5, 2018, to allocate pregnant women in Ecuador into three study arms: information only, soft commitment (i.e., a behavioral nudge), and financial incentives. All participants received an informational flyer, including the address of a testing location. Participants in the soft-commitment arm signed and kept a form on which they committed to get tested for HIV. Those in the financial incentive arm received a $10 incentive when tested for HIV. A stepwise logistic regression analysis estimated the effect of the study arms on HIV testing rate. Participants in the financial-incentive arm had higher odds of getting an HIV test (adjusted odds ratio 17.06, P < 0.001) as compared with information-only participants. Soft-commitment had the opposite effect (adjusted odds ratio 0.14, P = 0.014). Financial incentives might be useful in improving HIV testing among pregnant women, especially among those who might be at higher risk but who have not completed an HIV test.

Providing vouchers and value information for already free eye exams increases uptake among a low-income minority population: A randomized trial

We study whether vouchers without and with value information encourage attendance of already free follow-up appointments among low-income minority individuals referred for evaluation of possible eye disease. Between May 2017 and September 2018, 821 individuals referred from 114 screening events across Baltimore City were offered (1) standard referral for a free follow-up appointment and prescription glasses, (2) a paper voucher described as redeemable for free follow-up and prescription glasses, or (3) an otherwise identical paper voucher which also indicated the monetary value of the appointment ($250). Under all three conditions, all referred individuals received the same patient education, counseling, and appointment reminders. We find that vouchers without and with value information increase follow-up by 12.5 and 20.3 percentage points, respectively, corresponding to a 36% and 58% increase compared to the standard referral for free follow-up (i.e., without a voucher). We conclude that using vouchers is a promising, low-cost approach to increase uptake of already free health services, particularly when the vouchers also provide value information.

Nudging toward vaccination: a systematic review

Background

Vaccine hesitancy (VH) and the global decline of vaccine coverage are a major global health threat, and novel approaches for increasing vaccine confidence and uptake are urgently needed. ‘Nudging’, defined as altering the environmental context in which a decision is made or a certain behaviour is enacted, has shown promising results in several health promotion strategies. We present a comprehensive synthesis of evidence regarding the value and impact of nudges to address VH.

Methods

We conducted a systematic review to determine if nudging can mitigate VH and improve vaccine uptake. Our search strategy used Medical Subject Headings (MeSH) and non-MeSH terms to identify articles related to nudging and vaccination in nine research databases. 15 177 titles were extracted and assessed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The final list of included articles was evaluated using the Mixed Methods Appraisal Tool and the Grading of Recommendations, Assessment, Development and Evaluations framework.

Findings

Identified interventions are presented according to a framework for behaviour change, MINDSPACE. Articles (n=48) from 10 primarily high-income countries were included in the review. Nudging-based interventions identified include using reminders and recall, changing the way information is framed and delivered to an intended audience, changing the messenger delivering information, invoking social norms and emotional affect (eg, through storytelling, dramatic narratives and graphical presentations), and offering incentives or changing defaults. The most promising evidence exists for nudges that offer incentives to parents and healthcare workers, that make information more salient or that use trusted messengers to deliver information. The effectiveness of nudging interventions and the direction of the effect varies substantially by context. Evidence for some approaches is mixed, highlighting a need for further research, including how successful interventions can be adapted across settings.

Conclusion

Nudging-based interventions show potential to increase vaccine confidence and uptake, but further evidence is needed for the development of clear recommendations. The ongoing COVID-19 pandemic increases the urgency of undertaking nudging-focused research.

PROSPERO registration number

CRD42020185817.