Introduction

HIV infection continues to represent a global health problem, with 1.5 million incident cases and 680,000 AIDS-related deaths in 2020 [1]. One of the great challenges in facing the HIV/AIDS epidemic, in line with the “95-95-95” target proposed by the Joint United Nations Program on HIV/AIDS (UNAIDS) [2], is to increase the capacity for identification of new cases for early diagnosis and immediate treatment, helping to control the spread of the virus [3, 4]. In 2020, it was estimated that 16% of people living with HIV were unaware of their HIV status [5]. Cisgender men who have sex with men (MSM), transgender women (TGW), and other key populations are disproportionately affected by HIV, with much higher prevalence rates than in the general population in different regions and countries. Worldwide, it is estimated that around 70% of new HIV infections occur in people from key populations or their sexual partners [5,6,7,8], and approximately one third of MSM and TGW are not aware of their HIV status [9, 10], with a low proportion of testing in the last 12 months worldwide [11,12,13]. Assessing more vulnerable populations, including MSM and TGW, for the provision of testing and treatment services is a key task in controlling the HIV epidemic.

Structural and individual factors have been identified as barriers to testing among MSM, such as low perception of their own risk of infection, fear of a positive result, anticipation of HIV-related stigma, discrimination, and acceptance of sexual orientation, in addition to difficulties and dissatisfaction related to health services [14,15,16]. TGW, commonly included in the MSM group in epidemiological studies, are poorly studied in relation to their particularities and vulnerabilities to HIV [17, 18]. Stigma and discrimination related to gender expression and identity and other negative experiences in health services can make it difficult for TGW to access HIV testing services [13, 18,19,20,21].

Strategies for scaling up HIV testing in these key populations are critical, including health education actions with peer involvement, strategies based on social networks, use of self-testing for HIV, distribution of testing kits outside health facilities, awareness campaigns in media and public spaces, in addition to changes of traditional care models [22, 23]. These strategies may be influenced by several contextual and structural factors, such as internet access, cultural adequacy, availability of public services, and human resources [22, 23]. Analyzing the available evidence of the effectiveness of these strategies in an integrated manner is essential to point out potential knowledge gaps which may need to be addressed and develop public health policies to promote testing and early diagnosis of HIV infection. Thus, the present integrative review was carried out with the objective of identifying strategies for the promotion of HIV testing in populations of MSM and TGW.

Methods

Study population

This is an integrative literature review of original articles published until September 2021, without restriction of publication date or language, evaluating strategies to promote HIV testing among the MSM and TGW populations.

Types of study

Clinical trials (randomized and non-randomized), quasi-experimental studies, and observational studies, including case–control, cohort, cross-sectional and ecological studies, which presented at least two measures of the primary event (e.g., before and after the intervention) or assessment in two different periods, were included.

Qualitative studies, case reports or series, letters to the editor, review studies, and those that included data from the study population only in aggregate form were not considered in the review.

Types of HIV testing interventions

Studies that presented results of strategies implemented to promote HIV testing among MSM and/or TGW, whether or not compared with other strategies, were included. Strategies were classified into four main groups, according to the predominant characteristic of the intervention evaluated in the study: (1) self-testing delivery system; (2) organization of health services; (3) social marketing campaign; and (4) peer education.

Primary outcome

The primary study outcome was increase in HIV testing after an intervention strategy. Different measures of occurrence of the primary outcome (e.g. absolute number of tests, proportion and frequency of testing) used by the authors were considered.

Data collection and analysis

Electronic search

Searches were conducted in September 2021 in MEDLINE (via Ovid), Scopus, Sociological Abstracts (ProQuest), EMBASE, CINAHL, PsycINFO, Web of Science, and Global Index Medicus. The search strategy was carried out through a combination of free and indexed terms (Fig. 1), without restriction of publication date or language. Briefly, searches were performed using a combination of the following free and indexed terms and their respective synonyms, in addition to Boolean operators and truncation symbols: “HIV/aids; diagnosis/screening; testing; transgender; men who have sex with men”.

Fig. 1
figure 1

Strategy used to search for articles in the MEDLINETM (Medical Literature Analysis and Retrieval System Online) database via the OvidTM Platform

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Selection of studies

The screening of records retrieved from electronic searches, after removing the duplicates, were performed in two steps, using the RayyanTM platform (https://www.rayyan.ai/) and Microsoft ExcelTM software. The first step consisted of selecting articles by reading titles and abstracts. In the second step, a complete reading of the pre-selected articles in the previous step was carried out.

In both steps, the selection of articles was carried out in pairs (total of nine researchers: GMR, RCFC, NPC, EGAC, AAMC, IVM, MPCP, JAPJ, CMP) independently. Disagreements were resolved by a third review (CMP, GMR). The selection process was summarized based on the PRISMA 2020 recommendation (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) [24].

In the second step, the evaluation of the eligibility of the articles were ordered according to the following criteria: study design, intervention, comparison group, population, and outcomes, with the reasons for exclusion of studies duly documented and analyzed.

Data extraction

Data from the included studies were extracted using a standardized form containing relevant information in the following domains: information on publication, study design, participants, evaluation, and results of primary and secondary outcomes. Data were extracted in pairs independently. Disagreements were resolved by consensus. The information extracted from all studies was checked by a third reviewer. Data were analyzed descriptively, and relevant results were reported narratively.

Results

In total, 24,606 records were identified, and 13,793 were evaluated after removing the duplicates. After evaluating the titles and abstracts, 227 publications were considered potentially relevant, and it was possible to access 219 (96.5%) for full reading and eligibility assessment. Thirty-seven publications referring to 35 studies met the selection criteria and were included in this review (Fig. 2). A total of 182 publications were excluded due to ineligibility regarding the study design (n = 62), the intervention (n = 17), the comparison group (n = 3), the population (n = 29) or the evaluated outcomes (n = 71).

Fig. 2
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PRISMA diagram of studies searched and included in the review

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The included studies (n = 35) were published between 2006 and 2021, eleven being conducted in Asia (seven in China, two in India, one in Taiwan and one in Vietnam), ten in the United States of America (USA), six in Australia and five in Europe (four in the United Kingdom—UK and one in Spain). Two studies were conducted in Africa (Tanzania and Nigeria), and only one study was conducted in Latin America (Peru). All included studies were written in the English language. Most of the studies consisted of controlled trials (n = 22; 19 of which were randomized and three were non-randomized), and there were also three quasi-experimental studies. Thirteen observational studies were included, three of which were prospective cohort studies, one retrospective cohort study, eight cross-sectional studies, and one ecological study.

The main characteristics of the studies are presented in Table 1, organized according to the type of strategy evaluated to increase HIV testing: self-test distribution system (n = 9), organization of health services (n = 10), social marketing campaign (n = 10), and peer education (n = 6). The sample size of most randomized clinical trials (n = 19) was less than 500 participants, with great variability according to the sample unit (individuals or number of tests performed). In observational studies, the number of participants also varied widely (Table 1).

Table 1 Synthesis of the characteristics of the included studies according to the type of intervention
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All studies included only MSM as a target population, and we were not able to retrieve any study on TGW using the specified research strategy. In 15 studies, most participants were aged between 16 and 30 years old, while in twelve, the predominant group was older (> 30 years old). Information on sexual orientation was described in 18 studies, in which the majority of participants identified themselves as gay or homosexual (a proportion ranging from 58 to 94%). Among the included studies, 19 (54.3%) presented the results of positivity for HIV in the studied sample, which ranged from 0.23% to 15.50%, depending on the design, the inclusion criteria, and other methodological strategies adopted in each study.

Self-test distribution system

Eleven publications [25,26,27,28,29,30,31,32,33,34,35] from ten different studies (eight randomized controlled trials, one non-randomized clinical trial, and one retrospective cohort study) that evaluated different strategies for distributing and promoting self-testing in the MSM population were identified.

Zhu et al. [31] conducted a randomized clinical trial in China with MSM recruited from the community, commercial establishments, and on virtual social networks (68% aged between 18 and 29 years old). All study participants received two HIV self-test kits, and those in the intervention group additionally received access to a virtual platform (WeChat) via a cell phone application (WeTestApp) where they had access to videos, messages, and specific information about HIV prevention and testing. The proportion of testing was significantly higher in the intervention group compared to the control (92% vs. 68%; p = 0.004; Relative risk; 95% confidence interval—RR = 1.99; 95% CI = 1.03–3.84).

In another randomized clinical trial [30] involving MSM from the USA (mean age 35.5 years), participants in the intervention group received a kit to perform HIV self-testing at home, with the possibility of accessing a cell phone application to monitor testing, while those in the control group received a letter to get tested in a local clinic. In the intervention group, the proportion of testing was 100%, compared to 72% in the control group (p < 0.001).

MacGowan et al. [32] conducted a randomized clinical trial in the USA including MSM recruited from virtual platforms (social media, music and dating pages), where all participants had access to a database on remote testing and counseling by telephone. In the 12-month follow-up, the frequency of testing was higher among participants who received self-tests by regular mail (intervention group) than among those who underwent conventional face-to-face testing (control group) (mean of 5.3 and 1.5 tests, respectively; p < 0.001).

Another randomized clinical trial conducted in the USA [26] evaluated the effectiveness of the self-test strategy compared to usual testing among MSM (median age 35.5 years) at high risk of HIV infection recruited from sexual health clinics, social media, and web pages used by MSM. After a follow-up period of approximately 15 months, the mean number of tests was 5.3 in the intervention group and 3.6 in the control group (p < 0.0001).

In a non-randomized clinical trial conducted in the UK (37.0% aged between 45 and 64 years old), Vera et al. [27] evaluated the effectiveness of the availability of automatic vending machines for the sale of self-test kits on the frequency of testing among MSM users of saunas between September and December 2015. The intervention group (users of saunas with vending machines) performed 265 self-tests over the course of the trial (equivalent to 34 tests per month), while the control group (users of saunas without vending machines) underwent 40 tests performed by community professionals over the course of the trial (equivalent to 6 tests per month).

In the randomized clinical trial conducted by Jamil et al. [25] in Australia, participants (mean age 35 years) recruited from sexual health clinics, community organizations, social media, and web pages were allocated to the intervention group (free self-test kits and facility-based testing) or to the control group (conventional facility-based testing only) to assess the number of tests performed over 12 months of follow-up. Testing frequency was higher in the intervention group (701 tests; mean of 4.0 tests per year) than in the control group (313 tests; mean of 1.9 tests per year; p < 0.0001).

A randomized clinical trial conducted in China [28] evaluated three combined intervention strategies (online social marketing campaign, self-test delivery system with pre- and post-test guidance, and motivational interviewing) in the proportion of testing among 430 MSM during 6 months of follow-up. Participants were recruited from saunas, bars, and specific websites, with a predominance of age between 18 and 30 years old. In the group undergoing the intervention, 89.8% were tested for HIV, compared to 50.7% of the control group, which received only an online social marketing campaign (RR = 1.77, 95% CI = 1.54–2.03; p < 0.001).

A retrospective cohort study carried out in the UK [33] showed that between July and December 2017, fewer MSM used a system for dispensing HIV home testing kits via online ordering (n = 138), when compared to usual testing in health services (n = 1788). In contrast, a randomized clinical trial conducted by Rodger et al. [34] in the UK among MSM recruited in digital media found a significantly higher proportion of testing in the group that received HIV self-test kits, when compared with the control group (97% vs. 43%; p < 0.001). Similarly, a randomized clinical trial conducted in China [35] evaluated the effect of distributing HIV self-test kits compared to site-based testing on testing frequency over 12 months of follow-up. Higher frequency of testing was found among participants and their sexual partners in the intervention group (mean of 3.75 tests per participant and 2.65 tests per partner in the intervention group, compared to 1.80 per participant and 1.31 per partner in the control group; p < 0.001).

Organization of health services

Nine studies that evaluated strategies for scaling up HIV testing focused on the organization of health services (three randomized clinical trials, two non-randomized clinical trials, and four cross-sectional studies) [36,37,38,39,40,41,42,43,44].

In the study conducted by Read et al. [38] in a period of 12 months in Australia, no difference was observed in the frequency of testing between the intervention (HIV testing without going through a medical consultation) and control groups (medical consultation at each HIV test performed) (453 tests per 205.6 person-years vs. 432 tests per 204.0 person-years; RR = 1.04; 95% CI = 0.89–1.22; p = 0.63). In contrast, Snow et al. [37] observed an increase in the proportion of testing in a clinic after hiring a nursing professional who specialized in sexual health (57% vs. 37%; p = 0.026). Solomon et al. [39] observed a higher proportion of testing over 24 months in clinic-based services with integrated prevention, testing, and treatment actions focused on MSM, compared to services with conventional organization of care (with non-integrated actions) in India (33.9% vs. 25.2%; RR = 1.77; 95% CI = 1.30–2.41).

A cross-sectional study conducted in 23 testing and counseling centers in two municipalities in China [42] evaluated four different strategies for tracing sexual contacts of newly HIV-diagnosed MSM: (1) couples’ HIV counselling and testing (CHCT), when the index case was requested to return to the clinic with his sexual partner at a subsequent date to receive joint HIV testing and counseling; (2) information assisted partner notification (IAPN), with direct notification of the exposed partner by the health team; (3) assisted HIV self-testing (HIVST), when the exposed partner performed self-test after index case training; and, (4) patient referral (PR), with only reference and guidance from the partner exposed by the index case. Higher proportions of testing were observed in the IAPN, HIVST and PR groups (94.2%, 93.8% and 89.5%, respectively), compared to the CHCT group (82.2%). The increase in testing was significantly greater in the IAPN group, whose partners were notified directly by the healthcare team (RR = 3.9; 95% CI = 1.6–9.3).

A randomized clinical trial carried out in China [43] found a higher proportion of HIV testing among sexual partners of newly diagnosed HIV index cases who received an assisted reporting strategy (dispensing of self-test kits for the index case to pass on to the partner or notification by trained health professionals from community organizations), compared to those who received passive notification directly from the index case themselves (34% vs. 17%, respectively; p = 0.004).

A non-randomized clinical trial [36] evaluated whether offering HIV testing along with screening tests for a group of other conditions would increase HIV testing among Hispanic or Latino MSM who frequented gay bars in USA. The proportion of testing was slightly higher in the intervention group (10.2% vs. 8.9%), without showing statistically significant difference (RR = 1.59; 95% CI = 0.82–3.10).

Fernandez-Lopez et al. [40] evaluated the trend of HIV testing by MSM in a time series in Spain, and found an increased number of tests performed annually after the introduction of rapid testing in community testing services (from 167 to 380 annual exams between the years 1995 and 2006, to 1201 to 7988 annual exams between the years 2007 and 2018). Patel et al. [41] evaluated the potential effect of multiple government strategies on HIV testing coverage, including innovations in care routines, human resources development in health, expansion of testing modalities, and health promotion campaigns, in the period from 2010 to 2018 in Australia. Overall, the results showed a significant increase in the uptake of HIV testing among MSM who attended testing services (from 83.9% in 2010 to 95.1% in 2018; p < 0.001) and the average frequency of HIV testing (from 1.4 to 2.7 annual tests; p < 0.001). Similarly, a cross-sectional study carried out in Tanzania [44] evaluated the effect of a strategy based on a differentiated service delivery model, where health teams traveled to different regions of the country, in locations where the MSM community lived, worked or socialized, to promote HIV testing and counseling. The study showed a significant increase in the annual number of tests among the MSM population, from 1745 in the first year to 5081 in the second year, 6471 in the third year and 5165 in the fourth year of evaluation after the implementation of the strategy.

Social marketing campaign

Eleven articles from ten different studies evaluated the effect of social marketing campaigns on HIV testing [45,46,47,48,49,50,51,52,53,54,55], three of which were randomized clinical trials (USA, India, and Peru), two quasi-experimental studies (China and Australia), two cross-sectional studies (China and USA), two prospective cohort studies (UK and Taiwan), and one ecological study (Australia).

Five articles out of four studies conducted in Australia, China, and the United States [45, 47, 51,52,53], evaluated the effect of advertising campaigns, carried out both on virtual platforms and in person in the community, on the proportion or number of tests for HIV carried out in the respective localities. The interventions used printed educational material, audios, videos, dating mobile phone apps and specific internet pages aimed at the MSM population, with information on sexual health, HIV prevention, and testing. Wilkinson et al. [51] observed a progressive increase in the number of HIV tests over time in Australia, although there was a modest and non-significant increase in testing before and after the intervention (difference in the slope of the linear regression line of 1.7; 95% CI = 1.6–5.1). Tang et al. [52, 53] evaluated the increase in testing before and after carrying out multimedia campaigns associated with an online testing service and local testing promotion campaigns in eight cities in China. After 12 months of observation, the study reported that 62% of subjects underwent testing during the study period, with 53% during and after the intervention. Results from the intent-to-treat analysis showed that the probability of an individual testing for HIV during intervention periods (including post-intervention periods) was significantly higher than during control periods (RR = 1.43; 95% CI = 1.19–1.73; p < 0.001). Van Handel et al. [47] evaluated the effect of annual national campaigns on increasing HIV testing in the USA. The authors showed that the number of tests performed by the MSM population was significantly higher (p < 0.001) in the week of the educational campaign (n = 5919) when compared to the other weeks without intervention (n = 4124 and n = 4066). In contrast, Guy et al. [45] found similar proportions of testing before and after a specific advertising campaign (60.3% and 61.4%, respectively; p = 0.34) in sentinel clinics in Australia.

Among the included studies, six carried out advertising campaigns exclusively on virtual platforms as a strategy to increase HIV testing, with three randomized clinical trials (conducted in India, Peru, and the USA), two concurrent cohort studies (UK and Taiwan) and one cross-sectional study (China). In general, these studies used educational material (e.g., text messages and/or videos) in specific applications or websites aimed at the MSM population. Among clinical trials, Patel et al. [50] showed a slight increase in the proportion of testing in the intervention group after 3 months (31.5% vs. 41.8%; p = 0.04). Blas et al. [46] demonstrated some effectiveness in expanding HIV testing in the population that did not identify as “gay” (testing proportion of 11.8% in the group that received the intervention and zero in the control group; p = 0.001). In the study conducted by Bauermeister et al. [48], there was no significant difference in the proportion of testing between the two groups (31.5% vs. 25.9%; p = 0.27).

In the cohort study carried out by Hickson et al. [49], the effect of different educational health promotion strategies on the frequency of HIV testing among users of social networking sites was evaluated at three moments during the 13-month study. After seven months, the average annual number of tests per person was 1.67 among the exposed and 1.19 among the unexposed (RR = 1.37; 95% CI = 1.08–1.81; p = 0.03). After 13 months, the average annual number of tests per person was 1.60 among the exposed and 1.12 among the unexposed (RR = 1.48; 95% CI = 1.06–2.06; p = 0.02). In a prospective cohort study, Chiou et al. [55] found a higher proportion of testing among high-risk MSM in the intervention group (in which participants were recruited by social network platforms and tests were performed at a designated place by the participants) than in the control group (in which participants were recruited by a public website and tests were performed on traditional outreach screening station) (20.7% vs. 8.6%, respectively). Finally, the observational (panel-type) study conducted in China [54] showed a significant increase in the number of tests among the MSM population in the two years after a specific advertising campaign (carried out between 2015 and 2017), when compared to two previous years (836, 425, 3336, 6330 and 7315 tests were performed for HIV respectively in the years 2013, 2014, 2015, 2016 and 2017; p = 0.007).

Peer education

Six studies used peer education strategy to increase HIV testing [56,57,58,59,60,61], two with a cross-sectional design (Nigeria and Vietnam), a quasi-experimental study (USA), and three randomized clinical trials (USA). The average age of participants ranged from 19 to 37 years.

Rhodes et al. [58] evaluated the proportion of testing between the intervention (peer education in small groups, based on social cognitive theory, empowerment education, and traditional Hispanic/Latino cultural values) and control (general health education) groups over a six-month period in North Carolina, USA, and identified a significant increase in the proportion of HIV testing in the group that underwent the intervention (80.3%) compared to the control group (27.6%) (RR = 14.9; 95% CI = 7.56–25.33; p < 0.001).

Sabin et al. [61] evaluated the overall proportion of HIV testing after implementation of a community-based outreach program based on peer education in a community in Vietnam, identifying a significant increase in the overall proportion of testing after the start of the program (34.7% at the beginning of the program; 67.7% after using the strategy; p < 0.001).

Adebajo et al. [60] evaluated three distinct educational strategies carried out by peers for testing in decentralized community services in Nigeria (standard testing service, integrated mobile testing service, and peer testing service). HIV testing was significantly higher in the group that received the peer testing service when compared to the standard mobile testing service group (RR = 9.21; 95% CI = 5.57–15.23; p < 0.001).

In the randomized clinical trial conducted by Outlaw et al. [56] in the USA, researchers evaluated the effect of motivational interviewing delivered by trained peer outreach workers on testing among young MSM (mean age 19.8 years). The testing proportion was higher in the intervention group (49%) compared to the group that received only peer education actions (20%; p = 0.001).

Two studies, both conducted in the USA, adopted the peer education strategy exclusively on virtual platforms [57, 59] with a mean age between 30 and 40 years old. Young et al. [59] performed a randomized clinical trial that showed a higher proportion of HIV home self-test return among those exposed to peer-reported information related to HIV prevention and testing (15.8%), compared with those who received only general health information in online discussion groups (3.6%). Rhodes et al. [57] evaluated the proportion of testing in the last 12 months after the introduction of an educational intervention (based on social cognitive theory, empowerment education, and natural help) with guidelines related to HIV prevention carried out by peers on online relationship and message exchange platforms (chat). The proportion of HIV testing increased from 44.5% to 59.4% before and after the intervention, respectively (RR = 1.8; 95% CI = 1.4–2.5; p < 0.001).

Discussion

This study presents findings from a comprehensive integrative review to identify HIV testing promotion strategies targeted at MSM and TGW. The studies included in this review adopted strategies focused on self-test delivery systems, organization of health services, social marketing campaigns, or peer education. According to the results analyzed, each type of intervention has advantages and disadvantages, with potential specific recommendations for new actions and scientific research (Table 2).

Table 2 General summary of characteristics and recommendations by type of intervention
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Considering the knowledge gap on testing strategies aimed at TGW and the inadequacy of evaluating them together with the MSM group, it was decided to restrict the selection to exclusive studies involving the trans population. However, by the established search criteria, no studies with disaggregated data on TGW were identified, which points to the need for efforts to develop specific studies to reach and promote testing by the population of transgender women. The population of TGW has unique gender identities, social and behavioral vulnerabilities, such as stigma and discrimination, lack of social and legal recognition of their affirmed gender, and exclusion from employment and educational opportunities, leading to disproportionately low rates of HIV testing and high rates of HIV infection. Therefore, it is necessary to expand the field of HIV research and prevention actions specifically among trans population, avoid conflation of TGW with MSM in these strategies and addressing these trans-specific issues. [17,18,19]

Free of charge self-test distribution has been shown to be effective in promoting testing among MSM when combined [25, 27, 28, 30, 31, 35] or not [26, 32, 34] with other strategies. HIV self-test distribution strategy showed to be useful for high-risk and infrequent MSM testers, which has been thought to reduce operational barriers of clinic-based testing and stigma and discrimination [25, 26], as well for reaching MSM partners [35] and members of social network [32]. This is in line with what have been described that MSM have strong social networks [7].

By comparing HIV self-testing distribution to clinic-based testing, an important issue that emerged from the review is whether the self-testing strategy would complement [25, 35] or replace [26] the clinic-based testing, pointing out the potential for obtaining poor outcomes concerning sexually transmitted diseases testing and HIV transmission as well by the replacement with self-tests. The type and quality of the available products will play an important role in early HIV detection, acceptability, and willingness to test [25, 26, 31, 62,63,64]. Another concern regarding the strategy refers to the confirmation of positive results of self-tests, the occurrence of psychological harms in the absence of post-test counseling and the referral of MSM to health care [25, 27, 28, 32, 35]. It is possible to deal with these issues using communication technologies with remote face-to-face interaction, which can be a limiting factor due to the higher costs and difficulty of access [28, 30, 31].

Organization of health services included heterogeneous strategies organized and operated by the health services, addressing the MSM population in communities [36, 39, 44], in sexual health clinics, and testing and counseling clinics [37, 38, 42, 43] or in both clinical and community settings [40, 41]. In general, the provision of health services with integrated prevention, testing, and treatment actions provided by a trained multidisciplinary team can be effective in promoting testing, although it is necessary to expand access and use of these services by the MSM population, specially by subgroups that are more hidden and resistant to use health care facilities [37,38,39]. Moreover, well training professionals can increase testing rates for HIV and other STIs among MSM and partners of newly HIV-diagnosed patients, although this may incur higher costs [37, 38, 42, 43].

Strategies using social marketing campaigns resulted in an increase in the proportion of testing in two [46, 50] of the three randomized controlled trials evaluated. In general, these strategies should be performed periodically, as their efficacy tends to be more discrete and to decrease with time [45, 51], combining interventions on geosocial networking platforms and HIV testing service announcements [65], and including different social actors in its construction (e.g., members of key populations, lay people, and experts) [52]. Messages based on a gain–loss framework can be used, although the loss approach is indicated as more appropriate for the diagnosis (e.g., diagnostic tests), while the gain approach is better suited to prevention measures (e.g., condom use) [66]. These results reinforce the need to expand studies and propose new strategies that assess structural changes and other public policies in conjunction with health promotion actions to obtain better testing indicators [67].

Peer education has shown to be a potential strategy to increase HIV testing in the MSM population, despite the studies being heterogeneous in terms of methodology. In contrast, the evidence found for peer education on virtual platforms is fragile, considering the methodological limitations of quasi-experimental studies [57], due to the absence of randomization and a comparator group, in addition to sample size limitations [59]. It is noteworthy however, that most of the studies were published until 2015, a period in which the profile of use of digital social networks was different and interventions through these communication channels were less frequent.

Conclusion

The evidence of efficacy and effectiveness of strategies for increasing testing among MSM emerged from observation studies and controlled trials conducted in different settings. The findings cannot be directly extrapolated to other MSM populations due to cultural, social and economic specificities, in addition to methodological aspects of the studies that prevent generalization. Nevertheless, this integrative review provided a synthesis of the main strategies assessed worldwide and should contribute to the adoption of strategies in similar contexts. Research evaluating specific studies on TGW population is still needed.

Considering the diversity of proposed interventions and the methodological heterogeneity of the studies included in this review, it is recommended to evaluate strategies especially involving self-test distribution systems, associated with new information and communication technologies, applied in different communities and social contexts.