. 2023 Jun 26;76(3):e20210963. doi: 10.1590/0034-7167-2021-0963

Chart 2. Synthesis of studies included in the review according to year of publication and level of evidence, Ribeirão Preto, São Paulo, Brazil, 2022.

Authors, year and country of study	Objective of study	Population/sample studied	Method/strategy used	Main findings	LoE^*
Arnold et al., 2017⁽¹⁸⁾/ USA	Explore the structural, social, behavioral and clinical factors that affect PrEP use and retention in care.	Young MSM (n=30)	Qualitative/individual interviews	The main factors that affect PrEP use and retention in PrEP care include structural factors (cost, assistance with doctor visits and drug payments), HIV stigma and relationship status, partner’s HIV status, risky sexual behaviors and clinical factors (side effects).	V
Ellison et al., 2019⁽²⁰⁾/ USA	Assess barriers to oral PrEP and influences of sociodemographic characteristics and sexual behavior in choosing new drug formulations.	MSM (n=108)	Quantitative, cross-sectional/individual interviews	The listed barriers were daily PrEP regimen, difficult access to PrEP prescribers, difficulty making appointments, picking up prescriptions and talking to health professionals prescribing PrEP, racial and ethnic differences (Black and Hispanic men face more barriers compared to white and Asian men).	IV
Hunt et al., 2019⁽²¹⁾/ USA	Examine the challenges of accessing and complying with PrEP and to assess the usefulness of objectively monitoring PrEP compliance via urine.	Young adults (aged 18 - 34) using PrEP (n=40)	Quantitative, cross-sectional, descriptive	Participants reported being able to access PrEP quickly, but notable barriers reported included the unwillingness of the provider to prescribe PrEP. Regarding compliance, the most frequent barrier was remembering to take the medication.	V
Park et al., 2019⁽²²⁾/ USA	Characterize the path to PrEP gathering and continuity.	Black or Latina heterosexual cisgender women (n=14)	Qualitative	Misinformation about PrEP among healthcare professionals, concerns about medication safety, difficulty filling and withdrawing PrEP at pharmacies, out-of-pocket health costs.	V
Rice et al., 2019⁽²³⁾/ USA	Examine perceptions of access to PrEP.	Men who use PrEP (n=44)	Semi-structured individual interviews	The main barriers were cultural and social norms that silence the discussion about sexuality, lack of awareness and dissemination about PrEP, stigma related to sexuality, concerns about the adequacy and technical quality of PrEP services. The structural ones were long distances from health services, conflicting appointment times, medication costs, lack of health insurance resources, lack of knowledge of PrEP by health professionals, low perceived risk of HIV, concern about side effects.	V
Schwartz et al., 2019⁽²⁴⁾/ USA	Better understand the experiences of MSM in the adoption of PrEP.	MSM (n=38)	Qualitative/individual interviews	Stigma about PrEP from the very health professionals who provide PrEP, stigma of health professionals about homosexuality, social stigma about PrEP use being related to promiscuity, perception of discomfort of health professionals in talking about sexual health with gay men.	V
Sun et al., 2019⁽²⁵⁾/ USA	Identify barriers and facilitators to accessing PrEP.	Gay and cisgender men (n=27)	Qualitative	Long distances to access PrEP, living in a rural area, difficulty connecting to a PrEP prescriber, costs to buy the drug and interruptions in the supply of PrEP in pharmacies, long distances to access PrEP, living in a rural area, difficulty connecting to a professional PrEP prescriber, costs to purchase the drug, and interruptions in the supply of PrEP at pharmacies.	V
Wood et al., 2019⁽⁷⁾/ USA	Identify barriers and facilitators to HIV PrEP compliance.	MSM and trans women (n=31)	Nested mixed method with a prospective cohort	Stigma related to being mistaken for someone with a positive HIV status, HIV-related homophobia, stigma related to skin color, fear of having one’s sexuality revealed to one’s family, inaccessibility of health systems, side effects, stressors related to routine life and low perception of HIV risk.	IV
Laborde et al., 2020⁽²⁶⁾/ USA	Interpret the difficulties in PrEP persistence in a context of structural barriers, as well as clinical, pharmaceutical and interpersonal experiences.	Adult PrEP users (n=25) and health professionals prescribing PrEP (n=18)	Qualitative/individual interviews	Sexuality-related stigma, medical distrust, difficulty meeting PrEP follow-up requirements such as scheduling and attending routine appointments and laboratory tests, housing instability, substance use, mental health, difficulty communicating with providers. Getting refills from pharmacies was inconvenient and alienating for some participants.	V
Nieto et al., 2020⁽²⁷⁾/ USA	Explore reasons for discontinuing PrEP.	Black and Latino MSM and Black and Latino transgender women (n=22)	Qualitative/interviews with a semi-structured script	Lower perceived risk of HIV related to changes in sexual behavior, loss or change of health insurance, long distances to health services, difficulty attending routine appointments, anticipated and experienced adverse medication effects, fear of PrEP interaction with hormones or overloading the body with too many medications.	V
Nieto et al., 2020⁽²⁸⁾/ USA	Identify barriers and drivers for PrEP adoption.	Black and Latino trans women (n=18)	Qualitative/individual semi-structured interviews	Structural, logistical, linguistic, and cultural barriers to physician engagement, lack of competent transgender care, and prioritization of hormone therapy over PrEP use.
Owens et al., 2020⁽²⁹⁾/ USA	Raise barriers and facilitators to PrEP use.	MSM and who live in rural areas (n=34)	Quantitative/semi-structured interviews	Lack of rural dissemination of information about PrEP, health professional not informing about PrEP, concern about medication side and adverse effects, cost of PrEP compliance and involvement, lack of access to PrEP care and quality of care, especially in a rural environment.	IV
Camp & Saberi, 2021⁽³⁰⁾/ USA	Understand enablers and barriers to on-demand PrEP use and preferences for PrEP regimens, challenges to PrEP use during the pandemic.	MSM (n=140)	Cross-sectional, quantitative, with online data collection	Unplanned sexual encounters, difficulty remembering the dose, unpreparedness of the professional to provide PrEP care, the COVID-19 pandemic (difficulty in performing/obtaining laboratory tests, having PrEP refills, receiving a refill prescription from a healthcare professional, not being able to get a healthcare professional consultation, and not being able to communicate with your healthcare professional).	V
Felsher et al., 2021⁽³¹⁾/ USA	Describe the context of lives of people who use drugs and the challenges of compliance with PrEP.	Cisgender women who inject drugs (n=23)	Qualitative/individual interviews with semi-structured script	Difficulty meeting basic survival needs arising from the intersection of opioid use disorder, economic insecurity and housing instability, forgetting to take medication regularly, lack of secure storage of pills, loss or theft of pills, low self-efficacy, disabling structural factors (prescription drug market, drug treatment facility, or prison facility).	V
Jackson-Gibson et al., 2021⁽³³⁾/ Kenya	Explore enablers and barriers to PrEP implementation, acceptance and persistence.	Adolescent girls and young women (n=40)	Qualitative/individual interviews and focus groups	Side effects (lack of appetite, dizziness, nausea, vomiting, and stomach pains), PrEP-related community stigma, geographic distance to health facility, PrEP use associated with increased promiscuity, commercial sex workers, and people infected with PrEP HIV.	V
Kadiamada-Ibarra et al., 2021⁽³⁹⁾/ Mexico	Identify barriers and facilitators of a PrEP compliance program.	Male sex workers (n=8)	Quali-quantitative/individual interviews + focus groups	Lack of properly focused strategies to reach male sex workers, stigma related to HIV, PrEP use and key populations, geographic distance from PrEP facilities, lack of information about where to get PrEP and costs, lack of public policy, limitation of PrEP provision at ImPrEP sites and in implementation studies.	V
Kimani et al., 2021⁽³⁴⁾/ Kenya	Explore reasons for PrEP persistence.	Transgender women and men who have sex with men (n=53)	Mixed study/qualitative stage with semi-structured interview	Daily dosing schedule was a nuisance. Withdrawal of 90-day pills, negative reactions from partners and stigmatizing health services were considered barriers.	V
Koppe et al., 2021⁽³⁸⁾/ Germany	Analyze factors associated with stopping PrEP, barriers that may prevent people from continuing PrEP, and investigate sexual behavior after stopping PrEP.	Adults who used or were using PrEP (n=4,848)	Cross-sectional, quantitative/online data collection	The barriers described are often modifiable. Barriers were referred to as changing sexual partners, satisfaction with other prevention strategies, lower perception of risk of acquiring HIV, side effects, not wanting to take a chemical substance, fear of long-term side effects. Logistical barriers were difficulty obtaining PrEP, difficulty finding a doctor who prescribes PrEP, financial burden, and lack of health insurance coverage.	V
Ogunbajo et al. 2021⁽¹⁹⁾/ USA	Understand barriers to compliance experienced for PrEP use.	Black and Hispanic/Latino trans women and non-binary individuals (n=30)	Qualitative/individual interview	Concerns about costs, mental health issues, substance use, and concerns about PrEP side effects, including hormone interaction, intimate/romantic partner influence, and the impact of patient-professional communication, stigma, and negative community views related to PrEP, negative experiences in healthcare settings, unreliable transportation, employment, and housing insecurity.	V
O’Rourke et al., 2021⁽³⁵⁾/ Cape Town	Explore PrEP use experiences, including compliance and persistence or discontinuation experiences.	Adolescent girls and young women (n=22)	Qualitative prospective cohort	Pill-taking challenges, social opposition, or traumatic/unexpected event. Feelings of disappointment/failure regarding inability to continue PrEP use, PrEP-related stigma, decreased motivation, cultural issues such as conflict with coming-of-age traditions, lack of family support.	V
Sack et al., 2021⁽³⁶⁾/ Mozambique	Explore the perspectives, attitudes and experiences of HIV-serodiscordant partners taking PrEP.	People in HIV-serodiscordant relationships (n=19)	Qualitative/individual semi-structured interviews	The factors that influence PrEP compliance were divided into individual, interpersonal and organizational. Individual factors were love for the partner, knowledge about PrEP and belief that the drug is effective, and fear of HIV and PrEP stigma. Interpersonal factors affecting PrEP uptake were desire to protect family, partner support and relationship strength, overcoming fear of stigma to seek support from family and friends, and gender compliance approaches.	V
Stoner et al., 2021⁽³⁷⁾/ Cape Town	Understand patterns of decline in PrEP compliance in a prospective longitudinal cohort study.	Adolescent girls and young women (n=22)	Qualitative prospective cohort	Lack of family or partner support, traumatic events, and changes in the partnership. Decreased motivation, logistical barriers related to the health service, difficulty with the PrEP routine, forgetfulness, being busy, getting sick, changing residence, taking care of children, participating in cultural activities and difficulty in attending clinical appointments.	IV
Willie et al., 2021⁽³²⁾/ USA	Understand the multilevel factors that influence PrEP persistence.	Black cisgender women (n=8)	Qualitative/ individual interviews	Accessibility and costs of PrEP services, medication side effects (upset stomach, constipation, tachycardia and morning sickness).	V

LoE - level of evidence.