Erica Nicole Browne

BACKGROUND Smartphone-delivered ecological momentary assessment (EMA) is increasingly used as a mobile health (mHealth) tool to characterize substance use in real time, but its validity depends on survey completion being independent of the behaviors under study. If active substance use reduces the likelihood of responding to a mobile survey prompt, EMA-derived estimates may be biased. OBJECTIVE This study aimed to test whether momentary substance use was associated with survey-level noncompliance in a smartphone-delivered EMA protocol among people who use opioids. METHODS People who use opioids and other illicit drugs in Oakland, California (N=110) completed three EMA surveys daily for 28 days, recalling substance use since the prior survey prompt. Because each survey remained open until shortly before the next, reported use overlapped the previous response window. We identified 5,975 relevant survey pairs and used mixed effects modified Poisson models to estimate within and between person associations between substance use and missing the preceding survey. RESULTS On average, 87% of completed surveys included reports of substance use during the last survey’s response window. Within individuals, momentary polysubstance use was not associated with survey-level noncompliance. Only concurrent stimulant–alcohol use predicted within person noncompliance, which was associated with lower risk for noncompliance (RR 0.71; 95% CI 0.53, 0.96) compared to other substance use. Between individuals, those who used more types of substances on average were more likely to miss a survey. CONCLUSIONS Active substance use did not impede survey completion at the momentary level, supporting the validity of smartphone-based EMA in this population. Participants with more extensive polysubstance use profiles in general had higher noncompliance risk. Designers and analysts of mobile EMA protocols for substance-using populations should consider differential response rates linked to polysubstance-use severity and plan reminder schedules, incentive structures, or analytic adjustments accordingly. INTERNATIONAL REGISTERED REPORT RR2-10.1136/bmjopen-2023-075380

UNSTRUCTURED Background: In the study setting of western Kenya, as well as in sub-Saharan Africa more broadly, men are less likely to be engaged at each step of the HIV care cascade. Transactional sex constitutes a leading driver of HIV transmission between transactional and non-paying sexual partners, and men who purchase sex (MPS) represent a particularly high-risk and under-prioritized population. Data from South Africa estimates that sex between MPS and their non‐transactional female partners contributed 42% of all new HIV infections. Among women who sell sex (WSS) in Kisumu and Siaya Counties HIV prevalence is ~30%, and 65% of men report ever purchasing sex. This study seeks to identify and engage MPS in HIV services. Methods: This is a randomized stepped-wedge trial to evaluate whether the provision of multiple oral fluid-based HIV self-test kits to WSS to secondarily distribute to their male partners who purchase sex can promote HIV service uptake by male partners. The study will recruit 5,000 WSS in 25 clusters. Clusters will be randomized to the order in which they receive the intervention. Self-test kits will contain validated instructions for use and tailored information on clinics within the cluster, and empirically tested messaging on the benefits of ART for those who test positive and PrEP for those who test negative. The primary outcome will be the proportion of MPS who link to confirmatory testing in health facilities within study clusters during the intervention versus control periods. Secondary outcomes include the proportion of HIV case diagnoses, and ART or PrEP initiation among men. We will also analyze the cost-effectiveness of the intervention and conduct a process evaluation to assess mechanisms impacting intervention effectiveness, pathways for linkage among MPS, and support for men’s linkage to HIV services under a secondary distribution model. Discussion: Data generated from the study will provide evidence of the effectiveness of this HIVST secondary distribution intervention in identifying and engaging MPS in HIV testing, prevention and treatment services. If effective, this strategy can help in reaching men at elevated risk of HIV. Clinical trial registration: NCT05882916 (Reaching the Last 20% (the Pamoja Kwa Afya Study) | ClinicalTrials.gov). Date of registration: 26 May 2023.

Background: Oral pre-exposure prophylaxis (PrEP) is effective for HIV prevention , yet use has been inconsistent in adolescent girls and young women (AGYW). We compared PrEP with the dapivirine vaginal ring (ring) among AGYW in MTN-034 (REACH). Methods: We randomized 247 16–21-yr-old AGYW (South Africa, Uganda, Zimbabwe) to the sequence of using the ring and oral PrEP for 6 m each (February 2019–September 2021). Participants rated overall product acceptability (1, dislike very much to 5, like very much) after 3 m and 6 m, and product characteristics/use attributes after 3 m. We compared proportions of participants rating each product a “5” (binomial model with generalized estimating equations). We assessed associations between product characteristics/use attribute ratings at 3 m and overall acceptability after 6 m (χ ² ). Results:Overall,: 65% and 41% of participants rated the ring versus PrEP a “5” (adjusted risk difference [aRD] 24%, 95% CI: 15%, 32%; P < 0.001). For both products, high overall acceptability was associated with “excellent” self-rated adherence (ring, P < 0.001; PrEP, P = 0.03), product appearance (ring, P = 0.005; PrEP, P < 0.001), and ease of use (ring, P = 0.001; PrEP, P = 0.003). Not worrying about/or experiencing side effects were also associated with high acceptability of oral PREP. Conclusions: The dapivirine ring was highly acceptable to substantially more individuals than oral PrEP, although a significant minority rated oral PrEP highly, even after using the ring. As has been found in the contraceptive field, offering AGYW a choice of PrEP products is likely to increase the use of any HIV prevention method in this vulnerable population.

Background: Negative attitudes toward vaccines and suboptimal vaccination rates among African American and Black (Black) Americans have been well documented, due to a history of medical racism and human rights violations in the United States. However, digital health interventions (DHI) have been shown to address racial disparities in several health outcomes, such as cardiovascular disease, HIV, and maternal health. The Tough Talks COVID (TT-C) study was a randomized controlled trial of a DHI designed to empower Black young adults in the United States South to make informed, autonomous decisions about COVID-19 vaccine uptake by addressing structural barriers and misinformation about vaccines. Objective: Our objective was to identify subgroups of Black young adults with various vaccine attitudes at baseline and determine the subgroups for which the TT-C DHI was most impactful. Methods: Black young adults aged 18‐29 years in Alabama, Georgia, and North Carolina who were unvaccinated or insufficiently vaccinated against COVID-19 completed three online surveys over three months (N=360). Latent profile analysis was used to identify subgroups based on general vaccine attitudes at baseline, including hesitancy, confidence, knowledge, conspiracy beliefs, and mistrust. Logistic regression was used to examine the associations between latent profiles and vaccine uptake, and linear regression was used to examine changes in vaccine attitudes at three months post-randomization. Modification of the TT-C DHI’s effects was assessed by latent profiles. Results: Three latent profiles emerged: vaccine-receptive (n=124), vaccine-neutral (n=155), and vaccine-resistant (n=81). Political affiliation, income, social support, and recent flu vaccination differed significantly between the three subgroups (P<.05). Vaccine uptake was not significantly different by subgroup, and the TTC-DHI did not have differing effects on uptake across subgroups. However, the DHI had the strongest effect—with statistically significant measures of association (P<.05) and interaction P values (P<.10)—among the baseline vaccine-resistant and vaccine-neutral subgroups compared to the vaccine-receptive subgroups at three months in improving vaccine hesitancy, confidence, and conspiracy beliefs at three months: vaccine-resistant difference: −0.40 (−0.76 to −0.37), 0.39 (0.02 to 0.75), and −0.47 (−0.86 to −0.09); vaccine neutral difference: −0.36 (−0.52 to −0.19), 0.35 (0.18 to 0.51), and −0.24 (−0.44 to −0.03). The DHI had no effects on these outcomes among the vaccine-receptive subgroup. Conclusions: Our findings revealed subgroups of Black young adults in the United States South with different vaccination attitudes, for which the TT-C intervention had differing effects. Black young adults who are vaccine-resistant or vaccine-neutral may experience larger gains from a digital vaccine intervention. Future work aimed at improving vaccination outcomes could target these populations to maximize resource efficiency and drive the greatest improvements in vaccine outcomes.

Background: Adolescent girls and young women constitute a priority population disproportionately affected by HIV, accounting for 25% of annual HIV incidence among people older than 15 years in Kenya. Although oral preexposure prophylaxis (PrEP) is effective in reducing HIV acquisition, its protective benefit has been limited among adolescent girls and young women in sub-Saharan Africa because of low uptake, adherence, and persistence. Intimate partner violence (IPV) and relationship power inequities are widespread among adolescent girls and young women and contribute to higher HIV incidence and lower PrEP use. Interventions are needed to support sustained PrEP use among adolescent girls and young women by addressing IPV and relationship dynamics. Objective: This study aims to test the effectiveness of Tu’Washindi na PrEP (“We are Winners with PrEP”), a multilevel community-based intervention, to increase uptake and adherence to PrEP and reduce IPV among adolescent girls and young women in Siaya County, Kenya. Methods: The Tu’Washindi na PrEP intervention was co-designed by our team and adolescent girls and young women using participatory methods and includes 3 components delivered over 6 months: an 8-session, empowerment-based support club for adolescent girls and young women, community sensitization targeted toward male partners, and PrEP education events for couples. The intervention will be evaluated using a cluster randomized controlled trial across 22 administrative wards in Siaya County, Kenya, enrolling 72 adolescent girls and young women per ward (total N=1584). The primary objectives are to test the effectiveness of the intervention on PrEP uptake and adherence immediately after delivery (month 6 after enrollment) and 6 months later (month 12). As secondary objectives, we will test the intervention effect on IPV. A rigorous process evaluation will explore mechanisms of change, contextual factors, and implementation considerations to inform future refinement and scale-up, using programmatic data, participant questionnaires, and qualitative interviews with participants and intervention providers. Results: Data collection started in September 2022. As of December 2024, enrollment has been completed in 16 of the 22 study wards, with 72.6% (1150/1584) of participants enrolled. We anticipate that data collection will be completed in May 2026 and results will be available by mid-2027. Conclusions: The study builds directly on our promising formative and pilot research to develop the evidence base for this youth-designed, multilevel HIV prevention intervention. If effective, Tu’Washindi will be ideally positioned for sustainable integration into existing youth-focused programming to expand and support PrEP use in this priority population. Trial Registration: ClinicalTrials.gov NCT05599581; https://www.clinicaltrials.gov/study/NCT05599581 International Registered Report Identifier (IRRID): DERR1-10.2196/55931

Developmental scientists routinely examine how a focal predictor relates to some aspect of children's development. Although covariate adjustment is typically used to test hypotheses, propensity score-based methods, including inverse probability of treatment weighting (IPTW) and marginal structural models (MSM), can strengthen inference and answer more nuanced, developmentally relevant questions. This article provides a didactic introduction to IPTW and MSM methods and demonstrates their use for testing the impact of environmental smoke exposure (continuous treatment) from 6 to 90 months on parent-reported attention deficit hyperactivity disorder behaviors in first grade for 1,053 children (51% male, 44% Black) in the Family Life Project. We highlight differences that result both in conclusions and in the evaluation of assumptions for IPTW and MSM relative to more traditional covariate adjustment methods. Sample Stata syntax is provided. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

BACKGROUND Adolescent girls and young women constitute a priority population disproportionately affected by HIV, accounting for 25% of annual HIV incidence among people older than 15 years in Kenya. Although oral preexposure prophylaxis (PrEP) is effective in reducing HIV acquisition, its protective benefit has been limited among adolescent girls and young women in sub-Saharan Africa because of low uptake, adherence, and persistence. Intimate partner violence (IPV) and relationship power inequities are widespread among adolescent girls and young women and contribute to higher HIV incidence and lower PrEP use. Interventions are needed to support sustained PrEP use among adolescent girls and young women by addressing IPV and relationship dynamics. OBJECTIVE This study aims to test the effectiveness of Tu’Washindi na PrEP (“We are Winners with PrEP”), a multilevel community-based intervention, to increase uptake and adherence to PrEP and reduce IPV among adolescent girls and young women in Siaya County, Kenya. METHODS The Tu’Washindi na PrEP intervention was co-designed by our team and adolescent girls and young women using participatory methods and includes 3 components delivered over 6 months: an 8-session, empowerment-based support club for adolescent girls and young women, community sensitization targeted toward male partners, and PrEP education events for couples. The intervention will be evaluated using a cluster randomized controlled trial across 22 administrative wards in Siaya County, Kenya, enrolling 72 adolescent girls and young women per ward (total N=1584). The primary objectives are to test the effectiveness of the intervention on PrEP uptake and adherence immediately after delivery (month 6 after enrollment) and 6 months later (month 12). As secondary objectives, we will test the intervention effect on IPV. A rigorous process evaluation will explore mechanisms of change, contextual factors, and implementation considerations to inform future refinement and scale-up, using programmatic data, participant questionnaires, and qualitative interviews with participants and intervention providers. RESULTS Data collection started in September 2022. As of December 2024, enrollment has been completed in 16 of the 22 study wards, with 72.6% (1150/1584) of participants enrolled. We anticipate that data collection will be completed in May 2026 and results will be available by mid-2027. CONCLUSIONS The study builds directly on our promising formative and pilot research to develop the evidence base for this youth-designed, multilevel HIV prevention intervention. If effective, Tu’Washindi will be ideally positioned for sustainable integration into existing youth-focused programming to expand and support PrEP use in this priority population. CLINICALTRIAL ClinicalTrials.gov NCT05599581; https://www.clinicaltrials.gov/study/NCT05599581 INTERNATIONAL REGISTERED REPORT DERR1-10.2196/55931

Although stigma has been associated with people living with HIV defaulting from care, there is a gap in understanding the specific impact of individual stigma and community-level concern about HIV on defaulting. This is a secondary analysis of a unique dataset that links health facility-based medical records to a population-representative community survey conducted in 2018 in rural Mpumalanga province, South Africa. We used the parametric g-formula to estimate associations among individual anticipated stigma, low perceived community and local leader concern about HIV, and defaulting from care in the prior year. In addition, we estimated the population-level effects of intervening to reduce stigma and increase concern on defaulting. Among 319 participants on treatment, 42 (13.2%) defaulted from care during the prior year. Anticipated stigma (risk ratio [RR] 1.22, 95% confidence interval [CI]: 0.72, 2.74), low perceived concern about HIV/AIDS from community leadership (RR 1.12, 95% CI 0.76, 3.38), and low shared concerns about HIV/AIDS in the community (RR 1.37; 95% CI 0.79, 3.07) were not significantly associated with default. Hypothetical population intervention effects to remove individual anticipated stigma and low community concerns yielded small reductions in default (~1% reduction). In this sample, we found limited impact of reducing anticipated stigma and increasing shared concern about HIV on retention in care. Future studies should consider the limitations of this study by examining the influence of other sources of stigma in more detail and assessing how perceptions of stigma and concern impact the full HIV testing and care cascade.