Effect of Female Sex Work Targeted Community-based Interventions Along the HIV Treatment Cascade in Sub-Saharan Africa: A Systematic Review and Meta-analysis

Background: Female Sex Workers are extremely vulnerable and highly susceptibility to being infected with human immunodeciency virus. As a result, community based targeted interventions have been recommended as one of the models of care to improve access to HIV services and continued engagement in care. However little is known about the specic community intervention packages that have optimal effect on FSWs access and retention in HIV care. This paper synthesized evidence on the effectiveness of community-based interventions that provided HIV services to FSWs across all stages of HIV care cascade. Methods: We dened the 5 steps that make up the HIV care cascade and categorized them as outcomes, namely HIV testing, HIV diagnosis, linkage to care, ART use and viral suppression. We conducted a systematic search of randomized controlled trials, cohort and cross sectional studies done in sub-Saharan African countries and published from 2004 to 2020. We reviewed studies with data on the implementation of community interventions for any of the HIV care cascade stage. The data were analyzed using random effects meta-analysis where possible and for the rest of the studies, data were synthesized using summary statistics. Results: The signicant impact of the community interventions was observed on HIV testing, HIV diagnosis and ART use. However, for HIV testing and ART use, the improvement was not sustained for the entire period of implementation. There were minimal interventions that had impact on HIV diagnosis, with only one community service delivery model showing signicance. Generally, the interventions that had reasonable impact are those that implemented targeted and comprehensive package of HIV services provided at one location, and with unique strategies specic to each cascade stage. Conclusions: The effect of community-based interventions varies across the different stages of HIV care cascade with impact observed in specic strategies with features unique to each cascade stage. Moreover, positive effects of these strategies were short term and with small-scale implementation. As such, the information on long-term treatment outcomes, and the extent to which FSWs remain engaged in care is sparse. There is need to conduct a further research to deepen the assessment of the effectiveness of community-based interventions on HIV care cascade for FSWs. This will enhance identication of evidence based optimal interventions that will guide effective allocation of scarce resources for strategies that would have a signicant impact on HIV service delivery.

cascade with impact observed in speci c strategies with features unique to each cascade stage. Moreover, positive effects of these strategies were short term and with small-scale implementation. As such, the information on long-term treatment outcomes, and the extent to which FSWs remain engaged in care is sparse. There is need to conduct a further research to deepen the assessment of the effectiveness of community-based interventions on HIV care cascade for FSWs. This will enhance identi cation of evidence based optimal interventions that will guide effective allocation of scarce resources for strategies that would have a signi cant impact on HIV service delivery.

Background
Female Sex Workers (FSWs) are 21 times more susceptible to human immunode ciency virus (HIV) infection than other adults aged 15-49 years (1). On average HIV prevalence among FSWs is estimated to be approximately 12% globally (2). Findings from 26 countries with medium and high HIV prevalence in the general population indicate that 30.7% of FSWs are HIV positive (3) For example HIV prevalence among FSWs is estimated to be 33-36% (4) compared to 5.8% in the general population (1) and in Nigeria at 24.5% compared with 3.7% among adult population aged 15-49 years in both countries. HIV infection among FSWs is due to high prevalence of sexually transmitted infections (STIs) and unsafe sex practices with multiple sexual partners attributed to challenging economic circumstances (5,6). In addition, punitive environments such as violence, criminalization, stigma and discrimination, social and legal obstacles have been shown to limit access to services for HIV prevention, care, and treatment for FSWs (7,8). Various targeted intervention models of care have focused on FSWs with the aim of addressing poor access to HIV services and continued engagement in care (9)(10)(11)(12). In 2016, World Health Organization (WHO) disseminated consolidated guidelines for key populations including FSWs, with community-based approaches as one of the priority service delivery models (2). Further, in 2018, the WHO developed a decision framework on differentiated antiretroviral therapy (ART) and among other strategies, encompassed HIV community responses for FSWs (9). Among the different types of service provision, community-based service delivery approaches have gained more recognition as an evidence-based intervention to achieve positive health outcomes for FSWs (13,14). As such, many HIV/AIDS programs have implemented targeted community service delivery models and their effectiveness to reducing HIV risk among sex workers has been demonstrated (15,16).
However, to demonstrate the effectiveness of an HIV intervention depends on the ability to show that a particular intervention can increase access to prevention and treatment services across the treatment cascade (17). It is therefore critical to measure the performance of community-based interventions across the care and treatment cascade through a series of steps from access to HIV testing and receipt of an HIV positive diagnosis to successful treatment of their HIV infection. However, such an assessment has not been previously done, despite policy makers and donors appeal for HIV/AIDS response partners, to evaluate the effectiveness of interventions to guide resource allocation and scale up of high impact and sustainable service delivery models (18,19).
Community based interventions for FSWs have been assessed in only three previous systematic reviews (13,16,20). The rst review aimed to provide evidence on the impact of community empowerment for FSWs on condom use, HIV and other STI infection. The ndings showed that the targeted outcome measure on use of condoms and STI screening were signi cantly improved due to their association with community-based empowerment approaches (16). The second review assessed the barriers and facilitators of the implementation of FSW community empowerment programs (13). The decriminalization of sex work and building of social cohesion among FSWs were identi ed as facilitators while funding constraints were identi ed as hindrances to successful implementation. The third systematic review (20) described the nature and structure of targeted community empowerment sexual reproductive health (SRH) interventions, and their impact on HIV access for FSW. This review found that, although FSWs dedicated clinics had been established in proximity where FSWs lived and worked and somewhat increased access, very few provided a full package of SRH services for FSWs. All these reviews raised concerns regarding the weak quality of the evidence and recommended further research on the impact of community-based HIV interventions.
Based on the literature review ndings, the available systematic reviews have mainly focused on SRH services, and it remains unknown how community-based interventions have been impactful across the HIV treatment cascade. With the extensive recognition that community-based interventions for FSW are an important strategy in HIV response, it is critical to identify and evaluate the uniqueness of speci c interventions that may affect FSWs continuation in HIV care. None of the previous studies has systematically presented measurable outcomes attributed to the FSWs targeted community-based HIV interventions along the HIV treatment cascade. The goal of this, was to systematically review evidence on the effectiveness of community-based interventions that provided HIV services to FSWs by: 1) documenting improvement of HIV services access along the treatment cascade, 2) describing the community-based interventions that contributed to the proportion of FSW who: tested for HIV, got diagnosed and linked to care, initiated on ART and achieved viral suppression, 3) providing a systematic presentation of community-based interventions that positively impact continuation in HIV care across the HIV treatment cascade for FSWs in sub-Saharan Africa.

Methods And Design
The protocol for this systematic review was registered on Prospero, CRD42020157623 registration and published. The article can be accessed on http://bmjopen.bmj.com/cgi/content/full/bmjopen-2020-039495 De nition of FSWs community-based service delivery For the purpose of this systematic review the terms "community-based service delivery" and "community-based HIV interventions" were used interchangeably. We utilized a working de nition suggested by Moore (20) who de ned community-based interventions as services that are provided within geographical areas where FSWs live and work. The community-based services considered in this review were those that had been implemented in various ways including; i) those that provided supportive services to the public health facilities such as linking the clients to the health system for HIV care, ii) routine outreach services, iii) targeted FSWs clinics based in hotspots and, iv) stand-alone community services without a link to the formal public or private health facilities.

De nition of female sex work
In this review, FSWs were de ned as women who self-identify as sex workers and exchange sex for money, engage in transactional sex or exchange sex for other gifts and commodities.

Study design and setting
We included randomized control trials (RCT), cross-sectional surveys and cohort interventions conducted in sub-Saharan African countries from 2004 to 2020. We also reviewed unpublished quantitative data from reports and policy documents published within the region and period. The period was selected based on the time span within which ART was scaled up through widespread roll-out of comprehensive HIV programs in sub-Saharan Africa (19).

Study participants and intervention
To be included in the review, a study had to have evaluated a community-based HIV intervention for FSWs regardless of age and reported its effectiveness on one or more cascade stages. Studies that reported on community-based HIV services provided for FSWs in addition to other groups, were also included if data was disaggregated and reported by sex work status.

Outcomes
In order to be eligible for inclusion in the review, studies should have measured and reported the performance of the community-based HIV interventions at baseline/end-line or multi-arm design. Studies that had set performance targets for one or more treatment cascade stage and reported on outcomes post-intervention were also eligible. In this review, the HIV care cascade stages included HIV testing, HIV diagnosis, linkage to care, ART use and viral suppression. The outcomes were de ned following one of the two ways CDC monitors the continuum of care (21). We followed diagnosis-based HIV care continuum de nition that shows each step as a percentage of the number of people living with diagnosed HIV.
HIV testing was de ned as reported change (increase or decrease) in the number of FSWs that accessed HIV testing in a community-based HIV testing program; HIV diagnosis was de ned as the proportion of FSWs diagnosed with HIV among those tested; Linked to care was de ned as the proportion of participants who got diagnosed versus the proportion of those that accessed HIV care services, categorized as the completion of a rst medical clinic visit after HIV diagnosis; ART use was de ned as the proportion of participants who initiated ART, among those who tested HIV positive; and Viral suppression was de ned as the proportion of participants who attained viral suppression among those diagnosed with HIV.

Search strategy
We used a search strategy for electronic bibliographic databases, bibliographies of included articles, and grey literature sources. We developed a comprehensive set of search terms subjectively and iteratively, checking Medline (PubMed) through September 2020 to identify controlled vocabulary (MeSH) terms related to our topic, and identi ed keywords based on our knowledge of the eld. Medline search terms were adapted for other electronic databases to conform to their search functions. The following electronic databases were searched using the date range 2004 to present; Medline (PubMed), CINAHL (EBSCO Host), Science Citation Index Expanded (SCI-Expanded) and Social Sciences Citation Index (SSCI) both from the Web of Science, Scopus (Elsevier) and Cochrane Library, including the Cochrane Central Register of Controlled Trials (CENTRAL).
Websites of Joint United Nations Programme on HIV/AIDS (UNAIDS) and WHO were searched for additional reports of sex work programs. In addition to the electronic search, we searched for grey literature to identify any relevant unpublished reports. We also checked the reference lists of relevant articles for additional citations and used the "related citations" search key in PubMed where we identi ed similar papers. Search results were managed using specialized bibliographic software (Endnote).

Search terms
The following terms were entered into all data bases; HIV Infections[MeSH] OR HIV OR "hiv infect*" OR "human immunode ciency virus") AND ("HIV treatment cascade" OR "HIV continuum of care") AND ("Community Health Services"[Mesh]) OR "Delivery of Health Care" [Mesh] OR "Health extension worker*" or "Community led" OR "Community Implementer" OR "community worker*" OR "lay health worker*") AND ("Sex Workers"[Mesh] OR "Sex Work"[Mesh] OR prostitut* OR "exchanging sex" OR "sex trade ") AND ("Africa South of the Sahara"[Mesh] OR sub-saharan africa*)

Selection of eligible studies
Titles and abstracts were screened by two reviewers independently (LA, OA) and harmonized the differences by consensus on the studies eligible for full text screening. All full text articles were assessed for relevance by the same two reviewers independently (LA, OA), and determined nal studies that were eligible for inclusion for the systematic review. Disagreements were resolved by mutual consensus and by consultation with the third reviewer (PN).

Data extraction and management
Data were extracted using a standardized tool developed basing on the Cochrane format data collection form for intervention reviews (22). The developed tool was piloted by two reviewers (LA, OA) independently on a random sample of two articles, and the tool was revised accordingly. For all eligible studies, the same authors extracted data and jointly reviewed the extracted information for harmonisation. Discrepancies in the extracted data were resolved through discussion, consensus and involvement of a third reviewer (PN) when necessary.
The following information was collected from each included study; We collected data on study identi cation which included title, author and year of publication; Characteristics of studies such as study design, target group, description of interventions, type of comparison, type of outcome measures, unit of allocation (individuals or clusters), period of study, duration of follow up, setting including country of study ( locality and social context), method of participant recruitment, random or non-random allocation of participants, baseline imbalances, sample size and mean age. Other areas for which we collected data on, included interventions such as speci c type of community-based service delivery interventions per arm where it was applicable and co-interventions. We collected data on outcomes measures including number or proportions of FSW outcomes (HIV testing, HIV diagnosis, linked to care, ART use and viral suppression) at baseline and end-line and time points measured. There was also additional information collected on facilitators and challenges of implementing community-based interventions, and limitations of the studies.

Assessment of Risk of bias
Risk of bias for randomized controlled trials was assessed using an adapted Cochrane Collaboration's tool for assessing risk of bias. We used the tool to assess sequence generation, allocation concealment, blinding of participants and personnel, blinding of outcome assessment, incomplete outcome data, selective outcome reporting, and other sources of bias (22). For cross-sectional and cohort studies risk of bias was assessed and study quality rated using the adapted Newcastle Ottawa scale (NOS) (23). The Ottawa scale included the following items; (i) Representativeness of study sample and ascertainment of the exposure; ii) Comparability of cohorts on the basis of the design or analysis controlled for confounders; iii) Outcome assessment and adequacy of follow up period. Publication bias was assessed by visually inspecting funnel plot asymmetry and by including study size in the logistic model.

Data analysis
The data were analyzed using random effects meta-analysis. The main characteristics of included studies were synthesized using summary statistics to describe characteristics such as mean (standard deviation) and frequencies. For each step of the cascade together with the extracted community HIV service delivery interventions, the proportions with exact binomial 95% con dence intervals (CI) were calculated and presented in forest plots.
The homogeneity of the results was calculated by means of the Chi-square test and use the I 2 to describe the percentage variation across included studies. We planned to explore substantial heterogeneity (I 2 >50%) by subgroup analysis, however the ndings did not warrant this. All analyses were done in STATA version 16.0 (StataCorp. Stata Statistical Software: release 16. College Station, TX).

Summary of key ndings
Overall, this review found evidence on the impact of selected community-based intervention packages on FSW continuation in HIV care across the HIV care cascade. The signi cant impact of the interventions was observed on three cascade stages namely; HIV testing, HIV diagnosis and ART use. However, for HIV testing and ART use, the improvement was short-lived in that the retention on ART and improved access to HIV testing was not sustained for the entire period of implementation. There were limited impactful interventions for HIV diagnosis with only one community service delivery model showing signi cance. Generally, impactful interventions were those that implemented targeted and comprehensive package of HIV services provided at one location within places where FSWs worked and lived, and with unique service delivery models for speci c cascade stages. This review also found that community-based interventions led to the improvement of linkage to care and viral load suppression to undetectable levels, however, the improvement was not signi cant. In addition, the results showed that many of the projects were small-scale, research-based and have limited time-bound implementation periods. A few non-research based and large-scale HIV prevention efforts had limited systematic means of monitoring outcomes along the HIV care cascade and therefore, less methodical attention to constantly reviewing the effectiveness of interventions and altering delivery strategies accordingly.

Characteristics of included studies
Our literature search yielded 582 articles and after removing duplicates we remained with 565 studies.
Following screening of the titles and abstracts, we retained 45 studies for full text review. After thoroughly reading the remaining 45 articles, 27 studies were excluded for the following reasons; six articles had reported outcomes that did not meet our eligibility criteria, six did not meet the study design criteria, eight studies had not reported community based interventions, two articles were not written in English, two had either not targeted FSWs or not reported disaggregated data for FSWs, two articles were abstracts from conferences and we failed to access the required information, and one had not been conducted in Sub-Saharan Africa.
The remaining 18 studies were found eligible for inclusion in the review ( Table 1). The study designs were randomized controlled trials (n = 3), cross sectional studies (n = 10) and cohort studies (n = 4) and quasi experimental study (n = 1). These studies were conducted in seven sub-Saharan African countries ( Table 1).
Kelvin et al.
Pande et al.
HIV Diagnosis Enhanced peer outreach approach: • Use of paid out reach peers that have not worked as peers before to nd new FSWs from their network Napierala et al.

Risk of bias in included studies
The risk of bias in the included RCTs: Selection bias of allocation sequence generation was low in two studies and unclear in the remaining two. Allocation of concealment was unclear in three studies and low in one. In two RCTs, blinding of participants and personnel and blinding of outcome assessment was low and unclear in the remaining two studies. The risk of reporting incomplete data due to attrition and selective outcome reporting was low in three studies, high in one study and unclear in one study. The risk of bias in all RCTs was highest due to other forms of bias such that all had high risk due to reliance on self-report for outcomes, and short periods of intervention implementation with uncertain population effect. Other risk of bias were also related to low sample sizes including testing the intervention on limited number of FSW and FSW communities.
The risk of bias assessment in cohort studies: One cohort study had low risk of bias in relation to selection of representative samples and justi cation for case and control selection. However, for two cohort studies the risk of bias was unclear as information on justi cation for selection of control and cases was not provided. Never the less, both studies demonstrated that participants were not exposed to the intervention before the start of the study. All cohort studies had adequate measures of outcome assessment by using validated measurement scales, measurement of ART use by pill count rather than self-report and also had relatively long follow up periods of 6 to 12 months.
The risk of bias for cross-sectional studies: All the nine included cross-sectional studies had low risk of bias in regard to selection of sample size and its representativeness. However, the overall score between studies varied but the scoring grades weighed within the acceptable range of 4 to 6. In regard to risk of bias of assessing whether confounding factors were controlled, this information was not indicated in all the studies apart from one cross-sectional study which reported that a post-hoc pairwise comparison tests was conducted with RDSadjusted weights while adjusting for the confounding effect. Lastly, one study did not describe outcome assessment, therefore its risk of bias was unclear. However, in the rest of eight cross-sectional studies, risk of bias for outcome assessment was low as there was adequate description of the validated measures used to control for risk of bias. These included review of medical records, and health assessment by quali ed staff among others. All studies used statistical tests to control for bias in individual studies.
HIV testing services HIV testing was done in two randomized control studies conducted in Kenya (33) and Zambia (35). The Three cross sectional studies also reported HIV testing as an outcome (34,37,40). In a study conducted in Guinea (34)

HIV diagnosis
HIV diagnosis was measured in six cross-sectional studies (27,28,32,34,37,38), two randomized controlled trials (25,35) and one quasi-experimental study (39). The quasi-experimental study (Fig. 2) was conducted in three different countries (Burundi, Cote d'Ivoire and DRC) and measured the proportions of HIV seropositivity during the implementation of an enhanced peer outreach approach (EPOA) for the three countries. Pooled analysis of data from the three countries showed statistically signi cant increase in proportion of participants who tested positive (OR 2.23; 95% CI 1.23-4.05; p < 0.001). However, pooled analysis of data from two RCTs (Fig. 3) that randomized participants to standard of care testing versus general peer support augmented with additional community mobilization, showed that there was no signi cant improvement in HIV diagnosis among FSWs (OR 0.99; 95% CI 0.79-1.24; p = 0.307). Similarly, data from the pooled analysis of three cross-sectional studies (Fig. 4) showed that there was a reduction in HIV diagnosis tending towards the negative impact, outreaches in community settings as well as peer to peer mechanism ( Figure 6).

Viral suppression
Viral suppression was reported in three studies; two RCTs (25,29) and one cross sectional study (41). All the three studies reported data during implementation, while one RCT also reported effect at the end of follow up period (29). The RCT by Cowan (25) reported viral suppression rates for the participants that were assigned to clusters of usual care and those of the intervention clusters. At the end of the assessment period, 72% (588/828) in the intervention cluster, showed minimal difference in reduction of viral load to undetectable level less than 1000 copies per mL, compared with 68% (590/869) of the participants in the usual care clusters.
Similarly, the RCT by Kerrigan (29), the viral suppression rates showed slight improvement in the intervention

HIV testing
The ndings from this review on HIV testing show that community based interventions which increased access to HIV testing are those that applied combined strategies such as incentivized peer network referrals, intensi ed FSW mobilization, structured follow up to improve repeat testing, integrated health services adapted to speci c needs of FSWs such as placing lubricants in clinics and testing in static clinics based in hotspot (33)(34)(35). The trend of improvement however, was short-lived with proportions of testing reducing from 95% to 84% in just 4 months (35) and from 92% to 53% at one year follow up (34). According to these studies, the possible explanation for reduced proportions in testing over time was the saturation in target areas. However, the testing guidelines (2), indicate that FSWs should test every three months, therefore the explanation of saturation may not be satisfactory. There is need to investigate why the effectiveness of such interventions may not be sustained in order to create opportunities for designing optimal interventions.
This review complements other studies (42)(43)(44) which showed that strategies may not work separately but rather are more effective when combined. In this review, all studies whose control groups did not have any enhanced strategies, did not realize improved HIV testing access (33,35) although the rate of impact was the same across all interventions at the end of the follow up period (35). The enhanced and client centered approaches for improved HIV service access for FSW have been recommended to improve HIV response among FSW (2,9). However, we only found two research intervention studies (37,40) that involved FSW in the design and planning process of service delivery models; implying that client centered interventions are still minimal despite them being the recommended model of implementation for FSWs.
Although enhanced strategies that are community-based have proved to work, issues such as commodity stock outs, lack of consistency and low quality service provision in community programs have been identi ed as hampering progress (37,45). Such challenges are due to inadequate nancing of FSW programs (11). The success and expansion of community-based HIV programs for FSW requires concerted levels of efforts including the commitment of governments to increase nancing.

HIV Diagnosis
In regards to HIV diagnosis, the intervention that signi cantly identi ed more undiagnosed FSWs is the enhanced peer outreach model. This model involved training the FSWs that were naïve to peer network activities and used them to mobilize from their networks (39). This study was conducted in three countries; Burundi, Cote d'Ivoire and DRC with the hypothesis, that naïve peer network groups have different social networks that may be unreached by regular peer mobilisers. All the other studies in this review used the enhanced interventions similar to the ones used for HIV testing, however there was no increase in HIV diagnosis (25,28,32,34,35). With this nding, we emphasize that interventions are unique and may impact cascade stages differently. Therefore, to maximize impact, service delivery models need to be routinely monitored and reviewed to ascertain their effectiveness and revise the strategies accordingly.
The ndings in this review are related to other studies conducted in Ukraine (46) and Malawi (47) Linkage to care In this review we have documented that the data from pooled analysis showed no signi cant improvement in linkage to care. However, we note that programs that had a positive effect on linkage are those that provided a combination package of HIV services delivered in areas with close proximity to high concentrations of FSWs such as hotspots and drop-in centres alongside extended working hours during evenings, weekends and those that carried out sensitivity training for all the service providers (29,37). Previous reviews have indicated that, for optimal linkage to care, FSWs need to access comprehensive HIV services alongside structural interventions.
Such structural interventions include those that focus to address stigma and discrimination, violence prevention and legal challenges associated with practicing sex work (16,38,51,52). Notably, it was not clear whether such interventions were integrated in the service provision for FSWs in hotspots and drop in centres.
The nding that FSWs were fairly linked through hotspots based clinics and drop in centres has been associated with the favorable conditions such as ability to ensure con dentiality, use of professional and trained staff and provision of a range of health services (52). To augment such strategies with structural interventions, intentional provision of FSW-friendly services is required to support FSWs to navigate the health system with minimal stigma and discrimination tendencies. These ndings also indicate that irregular and mobile provision of HIV services poses challenges of follow up for linkage and retention. Health workers may not maintain constant engagement with FSWs and therefore there is need for strengthening the community systems that allow health workers and peers to constantly engage and provide HIV services in the community for FSW. Linkage is a very important stage in the cascade and therefore to optimize it, there is need to facilitate a robust comprehensive linkage and follow up system at both community level and facility level, so that cross linkages are streamlined enabling FSWs to get linked to care, stay in care and re-link those who drop out of care.
Use of anti-retroviral therapy Similar to other outcomes, effective interventions for ART also provided a broad package of interventions but the models in the speci c packages varied for each outcome. For example, ART use was improved if interventions were provided in the static facility services based in hotspots, but the services had to be provided on a daily basis, and on ex hours with room for phone consultation (37). In addition, ART use was improved by interventions that had adherence support and use of text message follow up as well as police sensitivity trainings to reduce violence (25,29,41). However, increased ART use could not be sustained up to the end of the follow up period (25,29,35). Notably, we found only one country, Zimbabwe; that had national program with dedicated FSW clinics (41). This nding implies that most of the interventions were on a small-scale and research-based with limited resources and this could possibly explain increased ART use was not sustained among FSWs.
Attaining short term ART use by FSW has been reported in another systematic review ( (2), could address the challenges of ART use among FSW if su cient resources are provided. The immediate treatment within test and treat mechanism allows prompt attachment to a peer network support system and other structural interventions and that would favor adherence support and hence sustained ART use among FSWs.

Viral suppression
In this review all the programs whose primary outcome was to improve viral suppression implemented interventions that strengthened engagement in HIV care by FSWs, however they did not lead to signi cant reduction in viral loads (25,27,29). Although non-signi cant, the effect showed a positive trend of undetectable viral load suppression resulting from the exposure to the interventions. Failure to attain signi cant improvements in viral load suppression could have been due to gaps in community systems for supporting adherence to ART reported in some of the studies (25,27).  The results of diagnosis could be due to the fact that participants allocated to the different models of interventions were somewhat dissimilar. Further, in this review we included studies whose primary aim was not to measure the effect of community intervention models, but rather we considered the reported results of our interest outcomes. For such studies, the effect may have been under or overestimated since critical observations on the processes of implementation were not emphasized. Finally, out of the 18 studies included in this review, only four were RCTs; we may therefore be underpowered to conclude on which models in a community-based interventions were more effective than the others.

Conclusion
Overall, the evidence brought forward from this review, shows that the effect of community-based interventions vary across the different stages of HIV care cascade. A broad package of interventions including a combination of behavioral, biomedical and structural, designed with speci c strategies, unique to each cascade stage appear to be more effective. Data suggests that there are limited community-based interventions that increase HIV diagnosis, however, a number of interventions are effective for HIV testing and ART use, and can also increase linkage to care and suppression although not signi cantly. This review also found that the positive effects of community interventions to increasing cascade outcomes are short term and the implementation is mostly done in research settings. As such, the information on long-term treatment outcomes, and the extent to which FSWs link to, adhere on ART and get virally suppressed is sparse.
This review observed challenges related to expanding the community-based interventions for FSWs, as majority of interventions were small-scale. Considerations for governments to strengthen support and integrate community-based HIV services in the mainstream health system are paramount. As countries roll out