Mixed-methods protocol for the WiSSPr study: Women in Sex work, Stigma and psychosocial barriers to Pre-exposure prophylaxis in Zambia

Abstract

Introduction

Women engaging in sex work (WESW) have 21 times the risk of HIV acquisition compared with the general population. However, accessing HIV pre-exposure prophylaxis (PrEP) remains challenging, and PrEP initiation and persistence are low due to stigma and related psychosocial factors. The WiSSPr (Women in Sex work, Stigma and PrEP) study aims to (1) estimate the effect of multiple stigmas on PrEP initiation and persistence and (2) qualitatively explore the enablers and barriers to PrEP use for WESW in Lusaka, Zambia.

Methods and analysis

WiSSPr is a prospective observational cohort study grounded in community-based participatory research principles with a community advisory board (CAB) of key population (KP) civil society organi sations (KP-CSOs) and the Ministry of Health (MoH). We will administer a one-time psychosocial survey vetted by the CAB and follow 300 WESW in the electronic medical record for three months to measure PrEP initiation (#/% ever taking PrEP) and persistence (immediate discontinuation and a medication possession ratio). We will conduct in-depth interviews with a purposive sample of 18 women, including 12 WESW and 6 peer navigators who support routine HIV screening and PrEP delivery, in two community hubs serving KPs since October 2021. We seek to value KP communities as equal contributors to the knowledge production process by actively engaging KP-CSOs throughout the research process. Expected outcomes include quantitative measures of PrEP initiation and persistence among WESW, and qualitative insights into the enablers and barriers to PrEP use informed by participants’ lived experiences.

Ethics and dissemination

WiSSPr was approved by the Institutional Review Boards of the University of Zambia (#3650-2023) and University of North Carolina (#22-3147). Participants must give written informed consent. Findings will be disseminated to the CAB, who will determine how to relay them to the community and stakeholders.

MEH and MM are joint senior authors.

STRENGTHS AND LIMITATIONS OF THIS STUDY

• The Women in Sex work, Stigma and PrEP (WiSSPr) study uses a mixed-methods approach which is ideal for intersectional stigma research because it allows quantitative research to be grounded in the lived experiences of people, while ensuring that aspects of stigma that emerge at the intersections of identities are measured in testable ways.

• Qualitative aim enrolls peer navigators to capture the perspectives of women who are at the unique interface of recipients of care as sex workers themselves, and supporters of health service delivery.

• Uses core principles of community-based participatory research which value key populations as equal contributors to the knowledge production process.

• Limitations include an inability to longitudinally assess the alignment of pre-exposure prophylaxis (PrEP) adherence and persistence with HIV risk, and limitations in measuring PrEP adherence by self-report and pharmacy dispensations instead of by drug biomarkers.

Introduction

Women engaging in sex work (WESW) are a key population (KP) that experiences an unacceptably high risk of HIV infection. In 2019, the Joint United Nations Programme on HIV/AIDS (UNAIDS) estimate WESW have 21 times the risk of HIV acquisition compared with the general population of adults aged 15 – 49 years old. ¹ In Southern and East Africa, KPs and their sexual partners account for 25% of all new HIV infections. ² To reduce the burden of HIV in Africa, HIV prevention strategies tailored to the unique needs of WESW are critical to safeguarding their health, as well as the health of people in their sexual networks. ^{3 4}

While HIV pre-exposure prophylaxis (PrEP) is highly effective in preventing HIV infection, its real-world efficacy is closely linked to adherence, which is a complex process for WESW. A systematic review of PrEP usage and adherence among WESW reveals complex interrelationships between individual perceptions of HIV risk, social support and fear of healthcare provider stigma. ⁵ WESW may experience multiple stigmatised identities, conditions or behaviours, such as participating in sex work, having a substance use disorder, and taking HIV prevention medication. ⁶

Zambia has a generalised HIV epidemic, and the capital city of Lusaka is a major regional transit hub attracting WESW from the region. Approximately 3,396 live in Lusaka with over half (53%) living with HIV, underscoring the need to urgently tailor prevention strategies for this population. ⁷ WESW in Zambia are subject to violence and discrimination in the form of verbal, physical and sexual abuse from strangers, acquaintances, clients, intimate partners and even law enforcement. ⁸ Surveys among WESW in Zambia have identified healthcare provider stigma and discrimination, as well as a lack of confidential care as main barriers to HIV prevention services at public health facilities. ^{7 9} Therefore, a better understanding of the multiple stigmas that WESW experience is a critical first step to designing interventions to meet their HIV prevention needs.

In recent years, Zambia has made significant progress in reaching WESW and providing them with comprehensive HIV prevention services. Since May 2019, the PEPFAR-funded Key Population Investment Fund (KPIF) has been successfully engaging with KP in Lusaka Province and providing them with community-based HIV prevention and treatment services. KPIF is implemented by the Centre for Infectious Disease Research in Zambia (CIDRZ) in partnership with the Zambian Ministry of Health (MoH), US Centers for Disease Control and Prevention and importantly, key population civil society organisations (KP-CSOs). A key objective of the KPIF programme is to improve PrEP initiation, persistence and adherence for HIV-negative WESW. For this study, we propose to leverage existing KPIF infrastructure to enhance study feasibility and ensure its real-world relevance to achieving this key objective.

Although PrEP initiations are high in the KPIF programme, they may not accurately reflect PrEP effectiveness.¹⁰ A systematic review of 41 studies found high discontinuation rates at 1 month.¹¹ Despite WHO recommendations and national PrEP guidelines for regular HIV testing and follow-up visits, maintaining client engagement with PrEP has been challenging.^{12 13} This has resulted in a lack of data on short-term PrEP persistence among WESW in Zambia. Assessing the percentage of clients who do not return for their first follow-up visit is crucial for determining PrEP effectiveness. Current prevention strategies do not adequately address the multiple stigmas and psychosocial stress that hinder PrEP persistence.

Specific objectives

The Women in Sex work, Stigma and PrEP (WiSSPr) mixed-methods study aims to (1) measure the association between multiple stigmas on PrEP initiation and persistence among HIV-negative adult WESW and (2) qualitatively explore the enablers and barriers (interpersonal, psychosocial and structural) to initiating and persisting on PrEP. The qualitative aim will complement and contextualise ^14–16 findings from the quantitative results. We hypothesize that WESW with high levels of any type of stigma will be less likely to initiate and persist on PrEP.

Conceptual framework

Interview guides will be informed by the Community, Opportunity, Motivation – Behaviour (COM-B) framework to assess how these components drive engagement with PrEP services.^{17 18} The COM-B model is commonly used in HIV prevention because it offers a framework to guide the development and implementation of targeted interventions, thereby enhancing the efficacy and reach of HIV prevention programmes.¹⁹ This framework will guide us to identify deficits in knowledge or skills (Capability), environmental and social contexts (Opportunity), and personal motivations and attitudes (Motivation). This integrated approach ensures that all relevant aspects of behaviour change are considered, leading to more effective and sustainable health outcomes.

Directed acyclic graph

Directed acyclic graphs (DAG) visually synthesise a priori knowledge about the hypothesised relationships between variables of interest, helping to identify causal pathways and potential confounders that could bias the results. We propose confounders based on their known association with stigmas and PrEP persistence, using evidence from published studies addressing similar questions. Controlling for the following variables will be sufficient to block any unconditionally open, non-causal backdoor paths that could lead to confounding: age, community hub, duration of sex work, and education (figure 1).

Figure 1. Directed acyclic graph illustrating the causal effect of stigma on PrEP persistence. PrEP, pre-exposure prophylaxis.

Methods and analysis

Study design

We will use a prospective observational cohort study design with mixed methods to characterise PrEP outcomes for HIV-negative WESW in Lusaka, Zambia. Trained research assistants will administer a one-time, 75-item psychosocial survey to participants and follow them prospectively in the electronic medical record. For the qualitative aim, we will conduct in-depth interviews (IDIs) with WESW to get perspectives of prevention services with peer navigators who are both recipients of care and supporters of health service delivery.

Mixed-methods integration

We will use the NIH ‘Best Practices for Mixed Methods’ guidelines to design, analyse and interpret qualitative and quantitative data in mixed-methods research.²⁰ Specifically, we will employ a convergent parallel design that collects both qualitative and quantitative data concurrently and separately, prioritising both the quantitative and qualitative strands equally but keeping them independent during analysis. We will interpret the extent to which the two sets of results converge, diverge, relate to each other and/or combine to create a better understanding in response to the study’s overall purpose.²⁰

Study setting

The study population is composed of adult WESW who are living or working within the catchment areas of two community hubs located within urban Lusaka. Based on CIDRZ’s prior published work, we anticipate that the study population will be comprised largely (63%) of younger women (18 – 29 years old). ¹⁰

Study exposures and outcomes

Table 1 identifies the primary outcomes of PrEP initiation and persistence from pharmacy dispensations records in the last 90 days for survey participants. Several studies have accessed this data from the national electronic medical record system SmartCare.^{21 22} CIDRZ is a key Smartcare implementing partner and routinely leveraging this data to optimise service delivery for KP in KPIF in order to better understand outcomes for HIV treatment and prevention in the national HIV programme.^23–28 Table 2 identifies the independent variables of interest including sociodemographic history, intersectional stigma (everyday discrimination scale),²⁹ substance use (ASSIST),³⁰ depressive symptoms (Patient Health Questionnaire, PHQ), ³¹ as well as sex work, HIV and PrEP-related stigmas and resulting discrimination using established questionnaires.^32–34 The qualitative outcomes are insights into the enablers and barriers to PrEP use informed by participants’ lived experiences according to the COM-B model.

Table 1

WiSSPr study outcomes

Outcome	Type	Definition
PrEP Initiation	Binary	Number of individuals initiated on PrEP/total number of HIV-negative individuals enrolled and eligible for PrEP.
PrEP Persistence	Binary, continuous	Immediate discontinuation for those who initiate a 30 day supply of PrEP and do not return for any refills over the 108 day observation period. Medication possession ratio of total days with medication in patient possession to the observation period, as a measure of engagement in services.

PrEP, pre-exposure prophylaxis; WiSSPr, Women in Sex work, Stigma and PrEP.

Table 2

WiSSPr study independent variables

Exposure	Type	Definition	Scale	Cut-off points	Survey section
Health services avoidance	Ordinal	Frequency of health services avoidance in the last 12 months	na	na
Health services delays	Ordinal	Frequency of health services avoidance in the last 12 months	na	na
Intersectional stigma	Categorical	Types of stigmatised identities, behaviours or conditions	Everyday Discrimination Scale	na	EDS
Discrimination due to intersectional stigma	Ordinal	General experiences of discrimination identities, behaviours or conditions	Everyday Discrimination Scale	na	EDS
Sex work experienced stigma	Ordinal	Experienced stigma from healthcare workers at any type of healthcare facility in the past 12 months	Sex Work Experienced Stigma Scale	na	SWES
Sex work anticipated stigma	Ordinal	Anticipated stigma of from family, community, healthcare workers, the police in the past 12 months	Sex Work Anticipated Stigma Scale	na	SWAS
Sex work internalised stigma	Ordinal	Internalised stigma of from family, community, healthcare workers, the police in the past 12 months	Sex Work Anticipated Stigma Scale	na	SWIS
HIV stigma	Continuous	Perceived stigma regarding people with HIV infection in general.	Likert scale	na	HST
PrEP stigma	Continuous	Perceived public stigma around taking PrEP	Likert scale	na	PRST
Depression	Ordinal	Minimal, mild, moderate, moderately severe, severe	PHQ	5, 10, 15, 20	PHQ
Suicidal ideation	Binary	Thoughts of hurting oneself or suicide	PHQ	na	PHQ
Alcohol use	Categorical	Moderate or high risk of alcohol use disorder	ASSIST	11, 27	AST
Substance use	Categorical	Moderate or severe risk of substance use disorder	ASSIST	4, 27	AST

ASSIST, The Alcohol, Smoking, and Substance Involvement Screening Test; AST, ASSIST; HST, HIV Stigma; na, not available; PHQ, Patient Health Questionnaire; PrEP, pre-exposure prophylaxis; PRST, PrEP Stigma; WiSSPr, Women in Sex work, Stigma and PrEP.

Sample size

We determined the minimum sample size using Demidenko’s method for logistic regression with binary interactions, informed by effect size and variance data from Witte et al’s study on PrEP acceptability among women in Uganda.^35–37 Sample size considerations are based on our primary outcome of PrEP initiation and informed by preliminary programmatic data that formed assumptions about baseline HIV prevalence and estimated PrEP initiations. Each site tests an average of 200 WESW per month, which will allow an estimated 800 women to be tested during the 2-month enrolment period. We project approximately 56% (448) will test HIV-negative, and of these, we estimate 403 (90%) will be eligible, and 350 (87%) will agree to initiate PrEP. Due to time and resource limitations, we seek to enroll a sample of 300 eligible WESW. Assuming 5% of participant medical records cannot be found, a total cohort of 285 PrEP users would allow us to estimate the prevalence ratio of stigma on PrEP initiation of 1.98 or higher (positive association), or 0.50 or lower (negative association) at 80% power with a significance level of 0.05. We aim to recruit 18 participants for IDIs, based on prior research with this population and qualitative methodology guidelines suggesting that 6 – 10 interviews per subgroup are sufficient to reach thematic saturation^{14 20}

Participant recruitment

The study will start in July 2023. WiSSPr will recruit 300 participants from a convenience sample of WESW who are receiving HIV services from two community-based hubs which have been functioning as MoH drop-in wellness centres since October 2021. All HIV testing and prevention services at these community hubs are led by teams of KP and MoH staff. Outreach activities take place in venues where WESW socialise, such as brothels, bars, or the home of a KP. Recruitment activities will take place during these outreach activities. KPIF programming leverages KP social networks to mobilise WESW for recruitment into the study. A total of 18 participants, including 6 peer navigators, 6 WESW who discontinue PrEP after initiation, and 6 WESW who continue on PrEP, will be purposively sampled for IDIs, or until we achieve thematic saturation.³⁸ Qualitative data collection will take place at least 30 days after the quantitative recruitment begins, in order to sample women who initiate a 30 day supply of PrEP but do not return to pick up another refill. Figure 2 outlines the WiSSPr study recruitment process.

Figure 2. The WiSSPr study flow diagram summarises the stages of participant recruitment and follow-up. PrEP, pre-exposure prophylaxis; WiSSPr, Women in Sex work, Stigma and PrEP.

Recruitment will end when 300 participants have been enrolled for the survey and 18 participants enrolled for interviews. PrEP event data will be abstracted from SmartCare approximately 3 months after the final participant’s enrollment. Study activities, including qualitative data collection, data quality control and assurance, and data analysis, are anticipated to continue until the planned end of the study in September 2024.

We will engage the community advisory board (CAB) in collaborative decision-making on: (1) how best to conduct outreach to venues that WESW frequent, (2) how to engage leaders in the sex work community to inform them about this study, and (3) to encourage WESW participation in a way that minimises social harms. Box 1 identifies the inclusion and exclusion criteria for the study. Written informed consent in English or local languages (ChiNyanja or IchiBemba) will be obtained before enrollment. As an added measure of protection for this marginalised population, participants must complete an informed consent quiz to ensure that they understand the potential risks of study participation. Participants will receive the Zambia Kwacha equivalent of US$5 per survey and interview as compensation for their time.

Box 1

Inclusion and exclusion criteria

Cohort inclusion and exclusion criteria are as follows:

• Inclusion criteria: (1) identify as a cis-gendered or transgendered woman, (2) age ≥ 18 years, (3) earns a significant amount of income from exchanging sex for money or goods in the last 3 months, (4) HIV-negative status and eligible for PrEP according to national guidelines, (5) not planning to transfer care to another site within the next 30 days, (6) speaks English or ChiNyanja or IchiBemba and (7) willing and able to provide written informed consent

• Exclusion criteria: (1) do not identify as a woman, (2) age < 18 years old, (3) has not earned a significant amount of income from exchanging sex for money or goods or has earned for < 3 months, (4) HIV-positive status or status is unknown or ineligible for PrEP, (5) planning to transfer care to another site within the next 30 days, (6) unable to speak English or ChiNyanja or IchiBemba and (7) not willing or able to provide written informed consent

In-depth interviews will be conducted with cohort members, as well as peer navigators. The inclusions and exclusion criteria for peer navigators is as follows:

• Inclusion criteria: (1) age ≥ 18 years old, (2) history working as a peer health navigator, (3) history of providing HIV services to women engaging in sex work, (4) speaks English or ChiNyanja or IchiBemba and (5) willing and able to provide written informed consent.

• Exclusion criteria: (1) age < 18 years, (2) does not have a history working as a peer health navigator, (3) does not have a history of providing HIV services to women engaging in sex work, (4) unable to speak English or ChiNyanja or IchiBemba and (5) not willing or able to provide written informed consent.

Quantitative data collection

A team of 3–5 trained research assistants will administer a tablet-based survey (online supplemental file 1) for quicker data entry, real-time quality control and logic checks to reduce data entry errors and immediate data backup compared with paper. Surveys, estimated to take 60 min each, will be conducted in English, ChiNyanja or IchiBemba, based on participant preference. The survey tool will be piloted with CAB members and peer navigators. Patient medical records are routinely entered by KPIF programme staff into a secure, standardised electronic data capture system, from which we will extract relevant deidentified data using the participants’ SmartCare ID numbers.

Qualitative data collection

We will use a semi-structured interview guide (online supplemental file 1) with open-ended questions and probes to explore specific themes related to HIV prevention and intersectional stigma. This guide allows some flexibility for participants to follow topics of interest to them. The themes we will explore are informed by the COM-B conceptual framework which include perceived and enacted stigma, the impact of intersectional stigmas on health service utilisation service needs, enablers such as psychosocial support or the trustworthiness of the healthcare system. The guide also includes modules on PrEP where the interviewer will explain oral and long-acting injectable PrEP and assess participants perceptions of the advantages and disadvantages and willingness to use these different PrEP options. Participants will be asked about their own perceptions as well as their perceived opinions of their peers, as this approach has yielded richer responses in previous studies.³⁹ Interviews are estimated to take 60 minutes and will be conducted in English, ChiNyanja, or IchiBemba in a private location at a community safe space or other similarly secure location determined by participant preference. We will request permission to audio record interviews for transcription and translation. All interviews will be conducted by a single trained interviewer. The interview guides will be piloted with CAB members before implementation.

Data management

SmartCare serves as a repository of clinical data for WESW accessing KPIF services. A secure server will be used to store encrypted study data, including the study database. Quantitative data collected on tablets will be transmitted to the server at the end of each day. To ensure data safety, there will be daily backups, and data will also be stored on secure drives.

All IDIs will be audio recorded. Audio recordings will be transcribed verbatim and then translated into English in a single step by qualified research staff. The audio recordings will not be marked with any identifying information. Instead, interviewers will use unique participant codes to label the audio recordings. No personal identifiers will be used, and any identifiers inadvertently mentioned during interviews will be purged from the transcripts prior to analysis.

All medical records that contain participant identities are treated as confidential in accordance with the Zambian Data Protection Act. All study documents related to the participants will only include an assigned participant code. Only research staff will have access to linkable information, which will be kept strictly confidential. All records will be archived in a secure storage facility for 3 years after the completion of the study per local regulatory guidelines, after which time all electronic data will be deleted from project servers and hard drives, and all paper-based records will be disposed of.

Quantitative data analysis

We will conduct univariable analyses to examine whether there are differences in the levels of stigma, discrimination, depressive symptoms and substance use disorders among those who initiate PrEP versus those who do not, stratified by community hub. We will report the prevalences of HIV and PrEP stigmas, discrimination due to intersectional stigma identified by the Everyday Discrimination scale, depression and suicidal ideation identified by PHQ, and substance use disorders identified by ASSIST. We will sum all items within a screener to a total score before collapsing data into categorical variables. For cases where missing data are more limited (approximately < 5%), for single items and measures, we will use mean imputation to derive a score. If there is substantial missingness (> 10%) then we will use missing data methods such as multiple imputation.

A PHQ-9 score ≥ 10 is commonly used in primary care settings as a cut-off for probable major depression.⁴⁰ PHQ-9 cut-off scores of 5, 10, 15 and 20 will be categorised as mild, moderate, moderately severe and severe depression, respectively. The ASSIST gives 10 risk scores for tobacco, alcohol, cannabis, cocaine, amphetamine-type stimulants, inhalants, sedatives, hallucinogens, opioids and other drugs. The score is higher the more frequently the participant reports using substances. For alcohol use, we will use cut-offs of 11 and 27 for moderate and high risk of substance use disorder. For all other substances cut-offs of 4, and 27 for moderate and high risk.³⁰

PrEP initiation will be calculated using the total number of individuals initiated on PrEP over the total number of HIV-negative individuals who were enrolled and eligible for PrEP. We refer to the complement of discontinuation as PrEP persistence.⁴¹ We define immediate discontinuation for those who initiate a 30 day supply of PrEP and do not return for any refills over the 108 day observation period in alignment with national antiretroviral therapy (ART) programme guidelines on continuity of care and management of missed appointments.^{21 42} We will calculate a medication possession ratio (MPR) of total days with medication in patient possession to the observation period, as a measure of engagement in services and report both the MPR and IQR (table 1).

We will use Stata (V.16.1, StataCorp) for analysis, reporting descriptive statistics to characterise the study population and bivariate associations between key exposures and immediate discontinuation with Pearson’s χ² statistics. We will fit Poisson regression models, which will estimate prevalence ratios of discrimination, PrEP stigma and HIV stigma on immediate discontinuation of PrEP over a 3-month follow-up period, controlling for confounders identified by the DAG. Adjusted prevalence ratio estimates will be reported with 95% CIs and p-values at the alpha = 0.05 significance level.

Qualitative data analysis

We will analyse the qualitative data using established analytical software (NVivo, QSR International, Melbourne, Australia) through deductive reasoning based on our conceptual model and inductive reasoning to identify major and minor themes emerging from audio recordings and transcripts. The process of eliciting themes will involve familiarisation with interview transcripts and noting emergent themes, adapting our conceptual framework as necessary, performing open coding, developing a codebook, performing data reduction, data display using matrices and/or tables, and interpretation to map out relationships in the data. Two coders will review these data, independently identify emergent themes, and confer to agree on final coding and findings. We will apply established qualitative research principles in our analyses, including negative case analysis and respondent validation.^{43 44}

Participant attitudes and preferences relating to elements of future stigma-reduction intervention, psychosocial support provision and long-acting injectable PrEP will be described qualitatively. We will strive for critical reflexivity by outlining our point of view in relation to the interviewees of the study during data collection and will state how positionality and context may have affected the findings. The credibility and trustworthiness of qualitative data will be assured through member-checking by participants themselves.⁴⁵

Ethics and dissemination

WiSSPr was approved by the Institutional Review Boards of the University of Zambia (#3650 -2023) and University of North Carolina, the Zambia National Health Research Authority and the Lusaka Provincial and District Health Offices. A final study notification will be sent on completion of the study, or in the event of early termination. Participants are free to withdraw from the study at any time without affecting their right to medical care.

The study findings will be disseminated to KP community members, providers, researchers and policy-makers. The CAB will review preliminary results and advise on meaningful dissemination to the KP community, National AIDS Council, National HIV and Mental Health Technical Working Groups, investigators and stakeholders. The information will be presented at conferences or published in peer-reviewed journals. Participants’ personal information will not be included in any publications.

Patient and public involvement

We will use principles of community-based participatory research (CBPR) to ensure patient and public involvement in this study. CBPR is a research paradigm that focuses on relationships between academic and community partners, with principles of co-learning, mutual benefit and long-term commitment.⁴⁶ CBPR incorporates community theories, participation, and practices into the research efforts and plays a role in expanding the reach of implementation science to influence practice and policies for eliminating health disparities.^{46 47}

To collaboratively develop this study with clients and the public, we will use CBPR principles and create a CAB with Lusaka District Health Office and two KP-CSOs working in the study sites: Zambia Sex Workers Alliance and Tithandizeni Umoyo Network. As a study team, our first priority is to develop trust with people engaging in sex work. Trust development is a construct of CBPR and has also emerged as a synthesising theory.^{48 49} Trust types are ordered along a relative continuum from least (trust deficit) to most (critical reflective) trust which reflects an ability to discuss and move on after a misstep.⁴⁸ Given the historical marginalisation and stigmatisation of WESW in Zambia, we anticipate a trust deficit and have allocated time and budget to nurture and develop trust along this continuum. We will build trust through ‘role-based trust’ as researchers, ‘proxy trust’ from the reputation of CIDRZ and KP CSO team members’ work with KPs in Zambia, and ultimately aim to establish ‘critical reflective’ trust.

The research questions and outcome measures were developed in collaboration with the CAB, ensuring they reflect the priorities, experiences and preferences of the sex worker community. Input from the CAB helped tailor the study to address the most pressing issues identified by the community. The study team will work with the CAB to adapt the study within complex systems of organisational and cultural context and knowledge. Collaborative decision-making will occur prior to the study launch, throughout the recruitment period, and during dissemination. The CAB will provide feedback on the potential burden of the intervention and the time required for participation, so that the study minimises inconvenience and respected participants’ time constraints. All partners will decide what it means to have a ‘collaborative, equitable partnership’ and how to make that happen. ⁵⁰ The CAB will advise on which community hub to recruit from first, and how to work with community leaders to adapt study standard operating procedures to not disrupt service implementation at study sites. They will also advise on how to minimise potential risks to participants, including ways to reduce emotional distress and ensure physical safety. Participants experiencing emotional distress will be referred for psychosocial support with evidence-based mental health therapy specialised for those with depression and substance abuse, with the KPIF providing transportation and a peer navigator accompanying them to the facility providing these services. The CAB will be actively involved in planning the dissemination of study results to participants and the wider community, helping decide what information to share, the timing of the dissemination and the most appropriate formats for communicating the findings.

Discussion

The WiSSPr study is significant as it addresses the limitations of HIV interventions that focus solely on HIV-related stigma, without considering co-occurring stigmas linked to other identities or conditions. This study will inform the design of PrEP service delivery programmes for WESW in Zambia and the region. Understanding stigmas and related psychosocial factors is crucial for developing effective, evidence-based stigma-reduction interventions for WESW in Africa. Our long-term goal is to optimise person-centred HIV prevention by implementing inclusive, affirming practices for individuals facing multiple barriers.

Strengths of this study include (1) a mixed-methods approach which grounds quantitative research in the lived experiences of people and measures aspects of stigma that emerge at the intersections of identities, (2) qualitative data from peer navigators capturing perspectives of women at the unique interface of being recipients of care as sex workers as well as direct supporters of health service delivery, and (3) incorporation of core principles of CBPR which value KP-CSOs as equal contributors to the knowledge production process.

Several methodological limitations are also inherent in the study. First, we are unable to longitudinally assess the alignment of PrEP adherence and persistence with HIV risk. We will be limited to measuring PrEP adherence by self-report and pharmacy dispensations instead of by biomarkers of tenofovir use. Secondly, recruitment might fall short at some sites, necessitating expansion to additional community outreach venues leveraging our network of KPs. Lastly, cohort studies may have bias, due to recall and social desirability bias of self-reported measures, and missing data.

The authors would like to acknowledge the infrastructure support provided by the Centre for Infectious Disease Research in Zambia (CIDRZ) and the Key Populations Investment Fund (KPIF) programme. The authors would also like to thank peer navigators and leaders in the sex work community for their assistance in developing the study approach and recruiting study participants.

Ethics statements

Patient consent for publication

Not applicable.

Footnote

X @idlidosa2, @kenmugwanya, @webarrington

Contributors RK, DR, AS, MM, MH, KKM and WB conceived and designed the study. RK, DR, AS, MM, MH, JP, MZ, MP, RZ, GMK, LC, PMK, CM and BN created the interview guides and survey. All authors revised drafts and gave final approval for publication. MM is the guarantor of the study and accepts full responsibility for the finished work and the conduct of the study, had access to the data and controlled the decision to publish.

Funding The study is being supported by the NIH Fogarty Global Health Fellowship awarded by the NIH Fogarty International Center Grant #D43TW009340.

Competing interests None declared.

Patient and public involvement Patients and/or the public were involved in the design, or conduct, or reporting, or dissemination plans of this research. Refer to the Methods section for further details.

Provenance and peer review Not commissioned; externally peer reviewed.

Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.

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