Parameters for sample size estimation from a group-randomized HIV prevention trial in HIV clinics in sub-Saharan Africa

Findings from the Tushirikiane mobile health (mHealth) HIV self-testing pragmatic trial with refugee adolescents and youth living in informal settlements in Kampala, Uganda

INTRODUCTION

Urban refugee youth remain underserved by current HIV prevention strategies, including HIV self-testing (HIVST). Examining HIVST feasibility with refugees can inform tailored HIV testing strategies. We examined if HIVST and mobile health (mHealth) delivery approaches could increase HIV testing uptake and HIV status knowledge among refugee youth in Kampala, Uganda.

METHODS

We conducted a three-arm pragmatic controlled trial across five informal settlements grouped into three sites in Kampala from 2020 to 2021 with peer-recruited refugee youth aged 16-24 years. The intervention was HIVST and HIVST + mHealth (HIVST with bidirectional SMS), compared with standard of care (SOC). Primary outcomes were self-reported HIV testing uptake and correct status knowledge verified by point-of-care testing. Some secondary outcomes included: depression, HIV-related stigma, and adolescent sexual and reproductive health (SRH) stigma at three time points (baseline [T0], 8 months [T1] and 12 months [T2]). We used generalized estimating equation regression models to estimate crude and adjusted odds ratios comparing arms over time, adjusting for age, gender and baseline imbalances. We assessed study pragmatism across PRECIS-2 dimensions.

RESULTS

We enrolled 450 participants (50.7% cisgender men, 48.7% cisgender women, 0.7% transgender women; mean age: 20.0, standard deviation: 2.4) across three sites. Self-reported HIV testing uptake increased significantly from T0 to T1 in intervention arms: HIVST arm: (27.6% [n = 43] at T0 vs. 91.2% [n = 135] at T1; HIVST + mHealth: 30.9% [n = 47] at T0 vs. 94.2% [n = 113] at T1]) compared with SOC (35.5% [n = 50] at T0 vs. 24.8% [ = 27] at T1) and remained significantly higher than SOC at T2 (p<0.001). HIV status knowledge in intervention arms (HIVST arm: 100% [n = 121], HIVST + mHealth arm: 97.9% [n = 95]) was significantly higher than SOC (61.5% [n = 59]) at T2. There were modest changes in secondary outcomes in intervention arms, including decreased depression alongside increased HIV-related stigma and adolescent SRH stigma. The trial employed both pragmatic (eligibility criteria, setting, organization, outcome, analysis) and explanatory approaches (recruitment path, flexibility of delivery flexibility, adherence flexibility, follow-up).

CONCLUSIONS

Offering HIVST is a promising approach to increase HIV testing uptake among urban refugee youth in Kampala. We share lessons learned to inform future youth-focused HIVST trials in urban humanitarian settings.

Positive deviance for promoting dual-method contraceptive use among women in Uganda: a cluster randomised controlled trial

OBJECTIVE

To examine the effects of a positive deviance intervention on dual-method contraceptive use among married or in-union women.

DESIGN

Open-label cluster randomised controlled trial.

SETTING

20 health facilities in Mbarara District, Uganda.

PARTICIPANTS

960 married or in-union women aged 18-49 years using a non-barrier modern contraceptive method.

INTERVENTIONS

A combination of clinic-based and telephone-based counselling and a 1-day participatory workshop, which were developed based on a preliminary qualitative study of women practising dual-method contraception.

PRIMARY OUTCOME MEASURE

Dual-method contraceptive use at the last sexual intercourse and its consistent use in the 2 months prior to each follow-up. These outcomes were measured based on participants' self-reports, and the effect of intervention was assessed using a mixed-effects logistic regression model.

RESULTS

More women in the intervention group used dual-method contraception at the last sexual intercourse at 2 months (adjusted OR (AOR)=4.12; 95% CI 2.02 to 8.39) and 8 months (AOR=2.16; 95% CI 1.06 to 4.41) than in the control group. At 4 and 6 months, however, the proportion of dual-method contraceptive users was not significantly different between the two groups. Its consistent use was more prevalent in the intervention group than in the control group at 2 months (AOR=14.53; 95% CI 3.63 to 58.13), and this intervention effect lasted throughout the follow-up period.

CONCLUSIONS

The positive deviance intervention increased dual-method contraceptive use among women, and could be effective at reducing the dual risk of unintended pregnancies and HIV infections. This study demonstrated that the intervention targeting only women can change behaviours of couples to practise dual-method contraception. Because women using non-barrier modern contraceptives may be more reachable than men, interventions targeting such women should be recommended.

TRIAL REGISTRATION NUMBER

UMIN000037065.

Mobile Health-Supported HIV Self-Testing Strategy Among Urban Refugee and Displaced Youth in Kampala, Uganda: Protocol for a Cluster Randomized Trial (Tushirikiane, Supporting Each Other)

BACKGROUND

HIV is the leading cause of mortality among youth in sub-Saharan Africa. Uganda hosts over 1.43 million refugees, and more than 83,000 live in Kampala, largely in informal settlements. There is limited information about HIV testing uptake and preferences among urban refugee and displaced youth. HIV self-testing is a promising method for increasing testing uptake. Further, mobile health (mHealth) interventions have been effective in increasing HIV testing uptake and could be particularly useful among youth.

OBJECTIVE

This study aims to evaluate the feasibility and effectiveness of two HIV self-testing implementation strategies (HIV self-testing intervention alone and HIV self-testing combined with an mHealth intervention) in comparison with the HIV testing standard of care in terms of HIV testing outcomes among refugee/displaced youth aged 16 to 24 years in Kampala, Uganda.

METHODS

A three-arm cluster randomized controlled trial will be implemented across five informal settlements grouped into three sites, based on proximity, and randomization will be performed with a 1:1:1 method. Approximately 450 adolescents (150 per cluster) will be enrolled and followed for 12 months. Data will be collected at the following three time points: baseline enrollment, 8 months after enrollment, and 12 months after enrollment. Primary outcomes (HIV testing frequency, HIV status knowledge, linkage to confirmatory testing, and linkage to HIV care) and secondary outcomes (depression, condom use efficacy, consistent condom use, sexual relationship power, HIV stigma, and adolescent sexual and reproductive health stigma) will be evaluated.

RESULTS

The study has been conducted in accordance with CONSORT (Consolidated Standards of Reporting Trials) guidelines. The study has received ethical approval from the University of Toronto (June 14, 2019), Mildmay Uganda (November 11, 2019), and the Uganda National Council for Science and Technology (August 3, 2020). The Tushirikiane trial launched in February 2020, recruiting a total of 452 participants. Data collection was paused for 8 months due to COVID-19. Data collection for wave 2 resumed in November 2020, and as of December 10, 2020, a total of 295 participants have been followed-up. The third, and final, wave of data collection will be conducted between February and March 2021.

CONCLUSIONS

This study will contribute to the knowledge of differentiated HIV testing implementation strategies for urban refugee and displaced youth living in informal settlements. We will share the findings in peer-reviewed manuscripts and conference presentations.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04504097; https://clinicaltrials.gov/ct2/show/NCT04504097.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/26192.

Positive deviance for dual-method promotion among women in Uganda: study protocol for a cluster randomized controlled trial

Background

Dual-method use is known as the most reliable protection against unintended pregnancies and sexually transmitted infections, including HIV. However, it is not commonly used in sub-Sharan Africa, especially among women using highly effective contraceptives. This article describes a protocol to evaluate the effect of an intervention formulated under the positive deviance approach for promoting dual-method use in Uganda.

Methods

A total of 150 women will be interviewed using a structured questionnaire to find those practicing dual-method use. In-depth interviews will then be conducted with all women using the dual method and 10 women using only highly effective contraceptives to identify their unique practice. Then, a cluster randomized controlled trial will be conducted to examine the effect of an intervention formulated under the positive deviance approach on dual-method uptake and adherence. Twenty health facilities will be randomized to an intervention or control arm and 480 women will be enrolled in each group. The participants will be followed up for 8 months.

Discussion

This trial focuses on women who already adapted dual-method use and identifies their unique solutions to promote dual-method use. This trial could tackle barriers for dual-method use, which expert outsiders may fail to recognize, by analyzing and promulgating their unique behaviors. This study could provide evidence that the positive deviance approach can address unintended pregnancies and sexually transmitted infections as well as other health problems which usual approaches have failed to address.

Trial registration

UMIN-CTR Clinical Trial, UMIN000037065. Registered on 14 June 2019.

Sample size estimation and re-estimation of cluster randomized controlled trials for real-time feedback, debriefing, and retraining system of cardiopulmonary resuscitation for out-of-hospital cardiac arrests

Background

In cluster randomized controlled trials (RCTs) for emergency medical services (EMS) system, we encounter the situation that the actual cluster size and ratio of allocated patients between two groups eventually differ from those used for sample size estimation because of the nature of patient enrollment. In such trials, estimations of effect size of test intervention and intra-cluster correlation coefficient (ICC) used for sample size estimation are also difficult. To improve efficient management on clinical cluster RCTs, we need to understand the effect of such inconsistencies of the design parameters on the type I error rate and statistical power of testing.

Methods

We planned the trial which evaluated the 1-month favorable neurological survival of out-of-hospital cardiac arrest patients with or without real-time feedback, debriefing, and retraining system by EMS personnel. Under the conditions that we possibly encountered in this trial, we examined the effect of inconsistencies in the actual ICC, cluster size, and ratio of patient allocation with those expected for sample size estimation on the type I error rate and power, using simulation studies. We further investigated the contribution of incorporating sample size re-estimation, based on the results of interim analysis of the trial, on the power increase.

Results

This simulation study showed that the inconsistencies of cluster size and patient allocation ratio decreased the power by 5-10% in some cases. In addition, the power decreased by 3-4% when the actual ICC was larger than that expected for sample size estimation. Furthermore, the use of a generalized estimating equation method to evaluate the difference in the 1-month favorable neurological survival between two groups caused inflation of type I error rate. Finally, the increase in power by incorporating sample size re-estimation was limited.

Conclusions

We identified remarkable effects of sample size estimation and re-estimations in a cluster RCT for real-time feedback, debriefing, and retraining system of cardiopulmonary resuscitation for out-of-hospital cardiac arrests. The estimation of design parameters for sample size estimation is generally challenging in cluster RCTs for EMS system; therefore, it is important to conduct a trial simulation that assesses the statistical performances under sample sizes based on the various expected values of the design parameters before beginning the trial.

Intra-Cluster Correlation Estimates for HIV-related Outcomes from Care and Treatment Clinics in Dar es Salaam, Tanzania

Introduction

Researchers planning cluster-randomized controlled trials (cRCTs) require estimates of the intra-cluster correlation coefficient (ICC) from previous studies for sample size calculations. This paper fills a persistent gap in the literature by providing estimates of ICCs for many key HIV-related clinical outcomes.

Methods

Data from HIV-positive patients from 47 HIV care and treatment clinics in Dar es Salaam, Tanzania were used to calculate ICCs by site of enrollment or site of ART initiation for various clinical outcomes using cross-sectional and longitudinal data. ICCs were estimated using linear mixed models where either clinic of enrollment or clinic of ART initiation served as the random effect.

Results

ICCs ranged from 0 to 0.0706 (95% CI: 0.0447, 0.1098). For most outcomes, the ICCs were large enough to meaningfully affect sample size calculations. For binary outcomes, the ICCs for event prevalence at baseline tended to be larger than the ICCs for later cumulative incidences. For continuous outcomes, the ICCs for baseline values tended to be larger than the ICCs for the change in values from baseline.

Conclusion

The ICCs for HIV-related outcomes cannot be ignored when calculating sample sizes for future cluster-randomized trials. The differences between ICCs calculated from baseline data alone and ICCs calculated using longitudinal data demonstrate the importance of selecting an ICC that reflects a study's intended design and duration for sample size calculations. While not generalizable to all contexts, these estimates provide guidance for future researchers seeking to design adequately powered cRCTs in Sub-Saharan African HIV treatment and care clinics.

Behavioral interventions for improving contraceptive use among women living with HIV

BACKGROUND

Contraception services can help meet the family planning goals of women living with HIV as well as prevent mother-to-child transmission. Due to antiretroviral therapy, survival has improved for people living with HIV, and more HIV-positive women may desire to have a child or another child. Behavioral interventions, involving counseling or education, can help women choose and use an appropriate contraceptive method.

OBJECTIVES

We systematically reviewed studies of behavioral interventions for HIV-positive women intended to inform contraceptive choice, encourage contraceptive use, or promote adherence to a contraceptive regimen.

SEARCH METHODS

Until 2 August 2016, we searched MEDLINE, CENTRAL, Web of Science, POPLINE, ClinicalTrials.gov and ICTRP. For the initial review, we examined reference lists and unpublished project reports, and we contacted investigators in the field.

SELECTION CRITERIA

Studies evaluated a behavioral intervention for improving contraceptive use for family planning (FP). The comparison could have been another behavioral intervention, usual care, or no intervention. We also considered studies that compared HIV-positive versus HIV-negative women. We included non-randomized studies as well as randomized controlled trials (RCTs).Primary outcomes were pregnancy and contraception use, e.g. uptake of a new method or improved use or continuation of current method. Secondary outcomes were knowledge of contraceptive effectiveness and attitude about contraception or a specific contraceptive method.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data. One entered the data into RevMan and a second verified accuracy. We evaluated RCTs according to recommended principles. For non-randomized studies, we examined the quality of evidence using the Newcastle-Ottawa Quality Assessment Scale. Given the need to control for confounding factors in non-randomized studies, we used adjusted estimates from the models when available. Where we did not have adjusted analyses, we calculated the odds ratio (OR) with 95% confidence interval (CI). Due to varied study designs and interventions, we did not conduct meta-analysis.

MAIN RESULTS

With three new reports, 10 studies from seven African countries met our eligibility criteria. Eight non-randomized studies included 8980 participants. Two cluster RCTs had 7136 participants across 36 sites. Three studies compared a special FP intervention versus usual care, three examined FP services integrated with HIV services, and four compared outcomes for HIV-positive and HIV-negative women.In four studies with high or moderate quality evidence, the special intervention was associated with contraceptive use or pregnancy. A study from Nigeria compared enhanced versus basic FP services. All sites had integrated FP and HIV services. Women with enhanced services were more likely to use a modern contraceptive method versus women with basic services (OR 2.48, 95% CI 1.31 to 4.72). A cluster RCT conducted in Kenya compared integrated FP and HIV services versus standard referral to a separate FP clinic. Women with integrated services were more likely to use more effective contraception (adjusted OR 1.81, 95% CI 1.24 to 2.63). Another cluster RCT compared an HIV prevention and FP intervention versus usual care in Kenya, Namibia, and Tanzania. Women at the special intervention sites in Tanzania were more likely to use highly effective contraception (adjusted OR 2.25, 95% CI 1.24 to 4.10). They were less likely to report unprotected sex (no condom use) at last intercourse (adjusted OR 0.23, 95% CI 0.14 to 0.40). Across the three countries, women at the special intervention sites were less likely to report any unprotected sex in the past two weeks (adjusted OR 0.56, 95% CI 0.32 to 0.99). A study in Côte d'Ivoire integrated HIV and FP services. HIV-positive women had a lower incidence of undesired pregnancy, but not overall pregnancy, compared with HIV-negative women (1.07 versus 2.38; reported P = 0.023).

AUTHORS' CONCLUSIONS

The studies since 2009 focused on using modern or more effective methods of contraception. In those later reports, training on FP methods and counseling was more common, which may strengthen the intervention and improve the ability to meet clients' needs. The quality of evidence was moderate from the more recent studies and low for those from the 1990s.Comparative research involving contraceptive counseling for HIV-positive women is limited. The FP field needs better ways to help women choose an appropriate contraceptive and continue using that method. Improved counseling methods are especially needed for limited resource settings, such as clinics focusing on people living with HIV.

Estimates of Intraclass Correlation Coefficients From Longitudinal Group-Randomized Trials of Adolescent HIV/STI/Pregnancy Prevention Programs

INTRODUCTION

Group-randomized trials (GRTs) are one of the most rigorous methods for evaluating the effectiveness of group-based health risk prevention programs. Efficiently designing GRTs with a sample size that is sufficient for meeting the trial's power and precision goals while not wasting resources exceeding them requires estimates of the intraclass correlation coefficient (ICC)-the degree to which outcomes of individuals clustered within groups (e.g., schools) are correlated. ICC estimates vary widely depending on outcome, population, and setting, and small changes in ICCs can have large effects on the sample size needed to estimate intervention effects. This study addresses a gap in the literature by providing estimates of ICCs for adolescent sexual risk-taking outcomes under a range of study conditions.

METHOD

Multilevel regression analyses were applied to existing data from four federally funded GRTs of school-based HIV/STI/pregnancy prevention programs to obtain a variety of ICC estimates.

RESULTS

ICCs ranged from 0 to 0.15, with adjustment for covariates and repeated measurements reducing the ICC in the majority of cases. Minimum detectable effect sizes with 80% power and 0.05 significance levels ranged from small to medium Cohen's d (0.13 to 0.53) assuming 20 schools of 100 students each.

CONCLUSIONS

This study provides the first known set of ICC estimates for investigators to use when planning studies of school-based programs to prevent sexual risk behaviors in youth. The results provide further evidence of the importance of using the appropriate adjusted ICC estimate at the design stage to maximize resources in costly GRTs.