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Li C, Thapa D, Mi Q, Gao Y, Fu X. Disparities in hepatitis B virus healthcare service access among marginalised poor populations: a mixed-method systematic review. Infect Dis Poverty 2024; 13:58. [PMID: 39123232 PMCID: PMC11312201 DOI: 10.1186/s40249-024-01225-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Accepted: 07/08/2024] [Indexed: 08/12/2024] Open
Abstract
BACKGROUND Marginalised poor populations, characterised by poverty and social exclusion, suffer disproportionately from hepatitis B virus (HBV) infections and encounter substantial disparities in access to healthcare. This has further exacerbated the global HBV burden and precluded progress towards HBV elimination. This mixed-method systematic review aimed to synthesise their utilisation and influencing factors in HBV healthcare services, including screening, vaccination, treatment, and linkage-to-care. METHODS Eleven databases were searched from their inception to May 4, 2023. Quantitative and qualitative studies examining the factors influencing HBV healthcare access among marginalised poor populations were included. A meta-analysis was conducted to synthesise the pooled rates of HBV healthcare utilisation. The factors influencing utilisation were integrated and visualised using a health disparity research framework. RESULTS Twenty-one studies were included involving 13,171 marginalised poor individuals: sex workers, rural migrant workers, irregular immigrants, homeless adults, and underprivileged individuals. Their utilisation of HBV healthcare ranged from 1.5% to 27.5%. Meta-analysis showed that the pooled rate of at least one dose of the HBV vaccine barely reached 37% (95% confidence interval: 0.26‒0.49). Fifty-one influencing factors were identified, with sociocultural factors (n = 19) being the most frequently reported, followed by behavioural (n = 14) and healthcare system factors (n = 11). Socio-cultural barriers included immigration status, prison history, illegal work, and HBV discrimination. Behavioural domain factors, including previous testing for sexually transmitted diseases, residential drug treatment, and problem-solving coping, facilitated HBV healthcare access, whereas hostility coping exerted negative influences. Healthcare system facilitators comprised HBV health literacy, beliefs, and physician recommendations, whereas barriers included service inaccessibility and insurance inadequacies. The biological and physical/built environments were the least studied domains, highlighting that geographical mobility, shelter capacity, and access to humanitarian health centres affect HBV healthcare for marginalised poor populations. CONCLUSIONS Marginalised poor populations encounter substantial disparities in accessing HBV healthcare, highlighting the need for a synergistic management approach, including deploying health education initiatives to debunk HBV misperceptions, developing integrated HBV management systems for continuous tracking, conducting tailored community outreach programmes, and establishing a human rights-based policy framework to guarantee the unfettered access of marginalised poor populations to essential HBV services.
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Affiliation(s)
- Caixia Li
- The Department of Nursing, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong Province, China
| | | | - Qian Mi
- The School of Nursing, Guangdong Pharmaceutical University, Guangzhou, China
| | - Yuanxiu Gao
- The Department of Nursing, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong Province, China
| | - Xia Fu
- The Department of Nursing, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong Province, China.
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Mayanja Y, Rida W, Kimani J, Ssetala A, Mpendo J, Nanvubya A, Mutua G, Anzala O, Price MA. Hepatitis B status and associated factors among participants screened for simulated HIV vaccine efficacy trials in Kenya and Uganda. PLoS One 2023; 18:e0288604. [PMID: 37459311 PMCID: PMC10351693 DOI: 10.1371/journal.pone.0288604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Accepted: 07/02/2023] [Indexed: 07/20/2023] Open
Abstract
INTRODUCTION Hepatitis B (HBV) prevalence remains high in Sub Saharan Africa and among some key populations such as those with continued exposure through sexual contact. We assessed the HBV status among potential participants who were screened for simulated HIV vaccine efficacy trials in Kenya and Uganda. METHODS We conducted a cross sectional analysis of data collected from individuals who were screened in Kenya (Nairobi) and Uganda (Entebbe and Kampala). The studies followed hypothetical procedures of an HIV vaccine efficacy trial and aimed to enroll HIV negative key and vulnerable populations at elevated risk of HIV acquisition. HBV status was the main outcome categorized using Hepatitis B surface antigen (HBsAg) and total Hepatitis B core antibody (HBcAb). Baseline characteristics potentially associated with never being infected were analyzed using logistic regression. RESULTS We screened 1,366 participants with mean age (SD) 28.7 (7.3) years. Overall, 46.6% were from Entebbe, 50.7% had secondary or higher level of education, 76.4% had informal high-risk jobs and 56.3% were male. Kampala had only female participants contributing 60.6% of females screened. Of the screened participants, 94.7% and 3.4% were negative and positive for HBsAg respectively. The prevalence on HBV infection was 3.9% among males and 2.8% among females while prevalence by site was: Entebbe (4.9%); Kampala (4.1%) and Nairobi (0.3%). The highest HBV prevalence was found among participants aged 25-29-years (5.2%), those with primary level education (4.5%), and those in informal low risk jobs (6.5%). Considering 1265 participants with complete data on HBsAg and HBcAb-Total, HBV status was never infected (67.9%), past infection (28.5%), chronic infection (3.2%) and acute infection (0.5%). Of 859 who were never infected, 685 (79.7%) were tested for anti-HBs titers of whom 60 (8.8%) had titers >10IU/L (immune due to vaccination). The odds of never being HBV infected were lower among older individuals 25-29 years (AOR 0.51; 95%CI 0.36-0.71) and ≥30 years (AOR 0.35; 95% CI 0.25-0.49). The odds were higher among participants with informal high-risk jobs from Kampala (AOR 2.21; 95% CI 1.41-3.47) and Nairobi (AOR 2.61; 95% CI 1.72-4.00) compared to those from Entebbe. CONCLUSION HBV prevalence and immunity due to vaccination were low among HIV negative individuals who are eligible for HIV vaccine trials and prevalence varies by age, education level and main occupation. Younger individuals and those recruited from existing cohorts/ clinics have a higher likelihood of having no prior HBV infection. HIV prevention intervention trials are a platform to identify individuals that need HBV vaccination.
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Affiliation(s)
- Yunia Mayanja
- Medical Research Council/ Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine (MRC/UVRI & LSHTM) Uganda Research Unit, Entebbe, Uganda
| | - Wasima Rida
- Biostatistics Consultant, Arlington, Virginia, United States of America
| | - Joshua Kimani
- SWOP-PHDA, University of Nairobi/University of Manitoba, Nairobi, Kenya
| | - Ali Ssetala
- Uganda Virus Research Institute/ International AIDS Vaccine Initiative (UVRI-IAVI) HIV Vaccine Programme, Entebbe, Uganda
| | - Juliet Mpendo
- Uganda Virus Research Institute/ International AIDS Vaccine Initiative (UVRI-IAVI) HIV Vaccine Programme, Entebbe, Uganda
| | - Annet Nanvubya
- Uganda Virus Research Institute/ International AIDS Vaccine Initiative (UVRI-IAVI) HIV Vaccine Programme, Entebbe, Uganda
| | | | - Omu Anzala
- KAVI- Institute for Clinical Research, Nairobi, Kenya
| | - Matt A. Price
- Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, CA, United States of America
- IAVI, New York, New York, United States of America
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Bell-Mandla N, Wilson E, Sharma D, Sloot R, Bwalya J, Schaap A, Donnell D, Piwowar-Manning E, Floyd S, Makola N, Nkonki L, Simwinga M, Moore A, Hayes R, Fidler S, Ayles H, Bock P. Predictors of participant retention in a community-based HIV prevention cohort: perspectives from the HPTN 071 (PopART) study. Trials 2023; 24:434. [PMID: 37370143 PMCID: PMC10294466 DOI: 10.1186/s13063-023-07404-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 05/23/2023] [Indexed: 06/29/2023] Open
Abstract
INTRODUCTION In 2021, there were 38.4 million people living with HIV (PLHIV) globally, of which 20.6 million (54%) were living in Eastern and Southern Africa. Longitudinal studies, inclusive of community randomized trials (CRTs), provide critical evidence to guide a broad range of health care interventions including HIV prevention. In this study, we have used an individual-level cohort study design to evaluate the association between sex and other baseline characteristics and participant retention in the HPTN 071 (PopART) trial in Zambia and South Africa. METHODS HPTN 071 (PopART) was a community randomized trial (CRT) conducted from 2013 to 2018, in 21 communities. The primary outcome was measured in a randomly selected population cohort (PC), followed up over 3 to 4 years at annual rounds. PC retention was defined as completion of an annual follow-up questionnaire. Baseline characteristics were described by study arm and Poisson regression analyses used to measure the association between baseline factors and retention. In addition, we present a description of researcher-documented reasons for study withdrawal by PC participants. RESULTS Of the 38,474 participants enrolled during the first round of the trial (PC0), most were women (27,139, 71%) and 73% completed at least one follow-up visit. Retention was lower in men (adj RR: 0.90; 95% CI: 0.88, 0.91) and higher among older participants (adj RR: 1.23; 95% CI 1.20, 1.26) when comparing ages 35-44 to 18-24 years. Retention was higher among individuals with high socioeconomic status (SES) (adj RR 1.16; 95% CI 1.14, 1.19) and medium SES (adj RR 1.12; 95% CI 1.09, 1.14) compared to low SES. The most common reasons for study withdrawal were study refusal (23%) and relocation outside the CRT catchment area (66%). CONCLUSION Despite challenges, satisfactory retention outcomes were achieved in PopART with limited variability across study arms. In keeping with other studies, younger age, male sex, and lower SES were associated with lower levels of retention. Relocation outside of catchment area was the most common reason for non-retention in this CRT.
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Affiliation(s)
- Nomtha Bell-Mandla
- Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Stellenbosch University, Cape Town, South Africa
| | - Ethan Wilson
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Deeksha Sharma
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Rosa Sloot
- Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Stellenbosch University, Cape Town, South Africa
| | - Justin Bwalya
- Zambia AIDS Related Tuberculosis Project, University of Zambia, Lusaka, Zambia
| | - Ab Schaap
- Zambia AIDS Related Tuberculosis Project, University of Zambia, Lusaka, Zambia
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | | | | | - Sian Floyd
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | - Nozizwe Makola
- Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Stellenbosch University, Cape Town, South Africa
| | - Lungiswa Nkonki
- Department of Global Health, Division of Health Systems and Public Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Musonda Simwinga
- Zambia AIDS Related Tuberculosis Project, University of Zambia, Lusaka, Zambia
| | | | - Richard Hayes
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | - Sarah Fidler
- Department of Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Helen Ayles
- Zambia AIDS Related Tuberculosis Project, University of Zambia, Lusaka, Zambia
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, UK
| | - Peter Bock
- Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Stellenbosch University, Cape Town, South Africa.
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Mutisya EM, Muturi-Kioi V, Abaasa A, Nyasani D, Kabuti RW, Lunani L, Kotikot T, Mundia M, Mutua G, Ombati G, Nduta H, Price MA, Kimani J, Anzala AO. Feasibility of conducting HIV prevention trials among key populations in Nairobi, Kenya. BMC Public Health 2022; 22:2385. [PMID: 36536335 PMCID: PMC9762985 DOI: 10.1186/s12889-022-14875-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVE To assess the feasibility of conducting HIV prevention trials among key populations in Nairobi, Kenya. BACKGROUND HIV prevention trials require the inclusion of those at high risk of HIV infection and their informed decision to take part and remain in the clinical trial to the end is crucial. In Kenya key populations including men who have sex with men (MSM) and female sex workers (FSW) are, disproportionately, at high risk of HIV infection when compared to the general population. Few trials testing biomedical prevention products against HIV have enrolled Kenyan FSW and MSM. METHODS We performed simulated vaccine efficacy trial (SiVET) using licensed hepatitis B vaccines as substitutes for a HIV vaccine candidate and included randomization for those immune to hep B. The SiVET was an observational study designed to mimic the rigors of a clinical trial; we assessed HIV risk, provided risk counselling and prevention tools and performed HIV testing at baseline and periodically until the end of the trial. MSM and FSW were enrolled at a ratio of 4:1. Volunteers were assigned to either hepatitis B vaccine or placebo. RESULTS Recruitment took approximately 24 months between Sep 2015 and Sep 2017. Of the 368 volunteers screened, 250 (200 MSM and 50 FSW) were enrolled. Reasons for exclusion at screening included: being positive for HIV (n = 7), hepatitis (n = 14), other pre-existing medical conditions (n = 41), eligible but chose not to enrol (n = 47). Most of the volunteers adhered to study procedures and attended their study visits within the study window. These include volunteers who received the second vaccination 244 (98%), the third vaccination 228 (91%) and, the final study visit 217 (87%). The reasons volunteers discontinued from the study early included: relocation and loss to follow up (n = 14). A total of 8 cases of HIV infection were observed in 174.5 Person Years at Risk (PYAR), all among MSM, including 5 seroconversions identified at the last study visit, for a HIV incidence of 4.58 cases/ 100 PYAR, among MSM enrolled in the study. CONCLUSION Our findings suggest that it is possible to conduct HIV prevention trials among key populations in Nairobi with a good adherence to a vaccine efficacy trial schedule. Despite HIV prevention efforts, we also noted a high incidence of HIV infection. This demonstrates the need for effective HIV prevention products in these populations.
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Affiliation(s)
| | | | - Andrew Abaasa
- MRC/UVRI and LSHTM Uganda Research Unit, Entebbe, Uganda
| | - Delvin Nyasani
- KAVI-Institute of Clinical Research, University of Nairobi, Nairobi, Kenya
| | - Rhoda W Kabuti
- SWOP-PHDA, University of Nairobi/University of Manitoba, Nairobi, Kenya
| | - Laura Lunani
- KAVI-Institute of Clinical Research, University of Nairobi, Nairobi, Kenya
| | - Timothy Kotikot
- KAVI-Institute of Clinical Research, University of Nairobi, Nairobi, Kenya
| | - Moses Mundia
- KAVI-Institute of Clinical Research, University of Nairobi, Nairobi, Kenya
| | | | - Geoffrey Ombati
- KAVI-Institute of Clinical Research, University of Nairobi, Nairobi, Kenya
| | - Hannah Nduta
- KAVI-Institute of Clinical Research, University of Nairobi, Nairobi, Kenya
| | - Matt A Price
- IAVI, New York, USA
- Department of Epidemiology and Biostatistics, University of California, San Francisco, California, USA
| | - Joshua Kimani
- SWOP-PHDA, University of Nairobi/University of Manitoba, Nairobi, Kenya
| | - Aggrey Omu Anzala
- KAVI-Institute of Clinical Research, University of Nairobi, Nairobi, Kenya
- School of Medicine, College of Health Sciences, University of Nairobi, Nairobi, Kenya
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Use of propensity score matching to create counterfactual group to assess potential HIV prevention interventions. Sci Rep 2021; 11:7017. [PMID: 33782485 PMCID: PMC8007631 DOI: 10.1038/s41598-021-86539-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 03/17/2021] [Indexed: 11/08/2022] Open
Abstract
The design of HIV prevention trials in the context of effective HIV preventive methods is a challenge. Alternate designs, including using non-randomised 'observational control arms' have been proposed. We used HIV simulated vaccine efficacy trials (SiVETs) to show pitfalls that may arise from using such observational controls and suggest how to conduct the analysis in the face of the pitfalls. Two SiVETs were nested within previously established observational cohorts of fisherfolk (FF) and female sex workers (FSW) in Uganda. SiVET participants received a licensed Hepatitis B vaccine in a schedule (0, 1 and 6 months) similar to that for a possible HIV vaccine efficacy trial. All participants received HIV counselling and testing every quarter for one year to assess HIV incidence rate ratio (IRR) between SiVET and non-SiVET (observational data). Propensity scores, conditional on baseline characteristics were calculated for SiVET participation and matched between SiVET and non-SiVET in the period before and during the SiVET study. We compared IRR before and after propensity score matching (PSM). In total, 3989 participants were enrolled into observational cohorts prior to SiVET, (1575 FF prior to Jul 2012 and 2414 FSW prior to Aug 2014). SiVET enrolled 572 participants (Jul 2012 to Apr 2014 in FF and Aug 2014 to Apr 2017 in FSW), with 953 non-SiVET participants observed in the SiVET concurrent period and 2928 from the pre-SiVET period (before Jul 2012 in FF or before Apr 2014 in FSW). Imbalances in baseline characteristics were observed between SiVET and non-SiVET participants in both periods before PSM. Similarly, HIV incidence was lower in SiVET than non-SiVET; SiVET-concurrent period, IRR = 0.59, 95% CI 0.31-0.68, p = 0.033 and pre-SiVET period, IRR = 0.77, 95% CI 0.43-1.29, p = 0.161. After PSM, participants baseline characteristics were comparable and there were minimal differences in HIV incidence between SiVET and non-SiVET participants. The process of screening for eligibility for efficacy trial selects participants with baseline characteristics different from the source population, confounding any observed differences in HIV incidence. Propensity score matching can be a useful tool to adjust the imbalance in the measured participants' baseline characteristics creating a counterfactual group to estimate the effect of interventions on HIV incidence.
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Mayanja Y, Abaasa A, Namale G, Price MA, Kamali A. Willingness of female sex workers in Kampala, Uganda to participate in future HIV vaccine trials: a case control study. BMC Public Health 2020; 20:1789. [PMID: 33239018 PMCID: PMC7686944 DOI: 10.1186/s12889-020-09932-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 11/18/2020] [Indexed: 11/30/2022] Open
Abstract
Background We anticipate large efficacy trials of novel HIV vaccines that have shown acceptable safety profiles. We determined willingness to participate (WTP) in future HIV vaccine efficacy trials among HIV negative female sex workers (FSWs) in Kampala Uganda. Methods We conducted a case control study in the Good Health for Women Project cohort. Cases received HIV prevention services and, enrolled in a 12-month simulated vaccine efficacy trial (SiVET) that used Hepatitis B vaccine; they underwent vaccine trial procedures as would be in an actual trial. Controls received similar health services but did not enroll in SiVET. We matched cases and controls (ratio 2:1) for age and duration in the cohort. We described a hypothetical HIV vaccine trial to cases (after 9 months in SiVET) and controls including trial attributes: randomization, delaying pregnancy, frequent blood draws (80-100mls) and study visits for 3 years. We compared WTP and willingness for vaccine trial attributes by case/control using chi-squared or Fisher’s exact tests and fitted conditional logistic regression models to determine independent predictors of WTP. Results We analyzed data for 311 volunteers (219 cases, 92 controls); median age 27 years (IQR: 23–32), 39.9% had ≥secondary education, 57.9% had sex work as their main job and 81.9% used illicit drugs. Compared to controls, more cases had lived in the community for > 1 year, (85.4% vs 64.1%; p < 0.001) and fewer cases reported illicit drug use in the past 3 months, (79.0% vs 89.1%; p = 0.03). Overall, 278 (89.4%) volunteers expressed WTP in an HIV vaccine trial, the most common reason being hope of protection against HIV. More cases than controls (58.2% vs 44.7%) did not need to consult anyone before trial participation (p = 0.03); cases were more willing to delay pregnancy (99.0% vs 94.0%; p = 0.03). Combining vaccine trial attributes, 249 (89.6%) of the 278 accepted all attributes. After controlling for case/ control status women with secondary education or higher expressed less WTP (aOR 0.17; 95% CI 0.04–0.80). Conclusion FSWs in Kampala demonstrated high WTP. Prior experience with trial requirements like contraception may improve their uptake during actual trials. Family involvement is important for those without prior trial experience.
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Affiliation(s)
- Yunia Mayanja
- MRC/UVRI & LSHTM Uganda Research Unit, Plot 51-59 Nakiwogo Road, Entebbe, Uganda.
| | - Andrew Abaasa
- MRC/UVRI & LSHTM Uganda Research Unit, Plot 51-59 Nakiwogo Road, Entebbe, Uganda.,London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Gertrude Namale
- MRC/UVRI & LSHTM Uganda Research Unit, Plot 51-59 Nakiwogo Road, Entebbe, Uganda
| | - Matt A Price
- IAVI, 125 Broad St, New York, NY, 10004, USA.,Department of Epidemiology and Biostatistics, University of California San Francisco, 550 16th Street, San Francisco, CA, 94143, USA
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Abaasa A, Nash S, Mayanja Y, Price MA, Fast PE, Kaleebu P, Todd J. Comparison of HIV Risk Behaviors Between Clinical Trials and Observational Cohorts in Uganda. AIDS Behav 2020; 24:2872-2884. [PMID: 32277309 PMCID: PMC7467908 DOI: 10.1007/s10461-020-02838-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Many key populations have high-risk behaviors for HIV infection making them suitable for HIV vaccine efficacy trials. However, these behaviors may change when participants enroll into a trial. We used HIV simulated vaccine efficacy trials (SiVETs) nested within observational cohorts of fisherfolks and female sex workers in Uganda to evaluate this difference. We screened observational cohort participants for enrolment into SiVETs, until 572 were enrolled. Those not enrolled (n = 953) continued participation in the observational cohorts. We determined risk behaviors at baseline and at 1 year, assigned a numeric score to each behavior and defined composite score as the sum of reported behaviors. We compared changes in scores over 12 months. Both observational cohorts and SiVETs saw a significant decrease in score but greatest in the SiVETs. Investigators recruiting for trials from these populations should consider the likely effect of reduction in risk behaviors on incident HIV infection and trial statistical power.
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