Abstract
Rationale & Objective
Latino individuals are poorly represented in dialysis research, and little is known about strategies to enhance Latino representation in dialysis research.
We sought to characterize the perceived barriers to and facilitators of research recruitment and retention through qualitative interviews with Latino participants receiving dialysis and community health workers (CHWS) who recruit Latinos for clinical trials.
Study Design
This qualitative study administered semistructured interviews, which were audio recorded, transcribed verbatim, and analyzed using thematic analysis.
Setting & Participants
Adult Latino individuals with dialysis-dependent kidney failure and CHWs with experience recruiting Latino individuals in clinical trial research from 2 urban dialysis centers in Denver, Colorado.
Results
We interviewed 13 Latino individuals with dialysis-dependent kidney failure (mean age 55 ± 7 years) and 15 CHWs (mean age 42 ± 13 years). We identified 5 themes (subthemes): valuing knowledge and empowerment (personal health benefit, gain knowledge about kidney disease, helping the community, and financial incentives), building trust between researchers and participants (clear communication about the study risks and benefits, understanding of culture and language, and incorporating family support), culturally concordant connection and respect (taking time to build personal connection, sincerity and warmth of connection, and approaching with respect and an equal footing), uncertainty and doubt about research (confusion about research concepts, discrimination, and language barriers), and conflicting priorities and burden of participation (physical impediments precluding participation, intruding on work priorities, and lack of transportation and phone communication).
Limitations
The study was limited to Denver and to participants who had participated in research.
Conclusions
Latinos are underrepresented in research, and an understanding of how to increase their participation is essential, especially in areas such as kidney failure, where they are over-represented as patients. The strategies identified in this study offer insights for augmenting representation of Latino participants in dialysis research, an essential step toward achieving health equity.
Index Words: dialysis, research, health equity, community health worker, clinical trials
Plain-Language Summary
Latino people are often missing from dialysis research. To better understand how to involve Latino patients in studies, we interviewed Latino dialysis patients who participated in research in the past and CHWs who recruit Latino patients for dialysis research. Participants noted willingness to join research when they feel it can improve their health, benefit their community, or offer financial support. Trust built through personal connection and respect, communication in Spanish, and family involvement was also important. However, confusion about research, past discrimination, health problems, work demands, and transportation difficulties made participation harder. These findings suggest that improving trust, communication, respect, and practical support may help increase Latino participation in dialysis research, potentially supporting more equitable health outcomes.
Latino (ie, Hispanic, including Latinx/Latina) people are the largest ethnicity group in the United States and are 2 times more likely to develop kidney failure compared with non-Latino people.1 Latino individuals, compared with non-Latino individuals, are also less likely to initiate dialysis with an arteriovenous access, utilize home dialysis, or receive a living donor kidney transplant.2, 3, 4 Many barriers to kidney care exist for Latino individuals, including lack of culturally and language concordant care, mistrust of and discrimination within health care systems, and lack of health insurance, limiting access to predialysis kidney care.5, 6, 7, 8, 9
Latino people are underrepresented in kidney research, representing 29% of the total dialysis population but only 13% of the participants in dialysis trials.10 Although this disparity has been attributed to lack of interest in clinical trials by Latino individuals, Latino individuals have reported willingness to participate in research when offered the opportunity11,12 but are often not asked.13 These findings suggest that underrepresentation of Latino individuals in research is not due to lack of interest, but rather these groups experience unique barriers to participation. Prior studies have identified barriers for participation in research of minoritized individuals, such as participant mistrust, lack of understanding of the research process, lack of awareness and information about the research, lack of a personal connection, and structural barriers such as lack of time and/or transportation.14, 15, 16, 17, 18 In addition, studies may not be culturally tailored to Latino populations. To-date, few studies have sought to understand and elucidate patient-informed strategies to overcome these barriers to research participation.
Community health workers (CHWs, or promotoras in Spanish) may represent one avenue for engaging underserved populations in research.19,20 CHWs are lay nonmedical individuals who are trusted members of the community and have share lived experience with the community they serve and, in other chronic disease populations, have been successful at engaging historically marginalized communities in research.20 We undertook this study to characterize the perceived barriers to and facilitators of research recruitment and retention among Latino individuals receiving dialysis and CHWs with experience enrolling Latino individuals in dialysis research.
Methods
Study Design
We conducted semistructured interviews with adult Latinos with dialysis-dependent kidney failure and CHWs to assess motivations as well as barriers and facilitators to recruitment and retention in research, operationalized as clinical trials for participants. We followed the consolidated criteria for reporting qualitative research in reporting this study.21 The Colorado multi-institutional review board approved the study. All participants provided informed consent and received renumeration.
Participants Selection and Recruitment
Eligible participants were adults (aged more than 18 years) who self-defined as Latino or Hispanic and who had hemodialysis-dependent kidney failure, and CHWs who had experience enrolling Latino or Hispanic individuals in research. We identified participants from 2 inner-city dialysis centers and a community steering committee composed of Latino individuals with hemodialysis-dependent kidney failure and caregivers in Denver, Colorado. Participants were sampled purposively to capture a range of experience, gender, and age.
Data Collection
The semistructured interview guides (Items S1 and S2) were informed by a literature review regarding prior barriers and facilitators to recruitment and retention of Latino individuals in research in dialysis14,15,17,18 and known barriers to kidney care for Latino individuals.5, 6, 7, 8,22 Questions were developed iteratively, and interviews were conducted in person or over the telephone in the participant’s preferred language (Spanish or English) by an experienced bilingual interviewer who was unknown to the participants. If a participant missed their interview time, one attempt was made to reschedule. Interviews took place in April and May 2024 and were continued until thematic saturation, when no new concepts were identified.23
Analysis
Interviews were audio recorded, transcribed verbatim, professionally translated to English, deidentified, and imported to qualitative data analysis software (Atlas.ti, version 9.22 [Scientific Software Development]). Interview data were analyzed inductively for themes by three independent coders (A.J., K.R., and S.V.), who have experience in qualitative research, until consensus was researched. Utilizing grounded theory,24, 25, 26 a theoretical framework was developed until consensus on themes and subthemes was reached, and the thematic analysis reflected the full range and depth of the data.26,27
Results
Interview participants included 13 individuals receiving dialysis who identified as Latino (Table 1) and 15 CHWs with experience enrolling Latino individuals in research (Table 2). Individuals who were categorized as declined (n = 11) were those who missed their interview appointment and did not follow up (n = 2), did not have time (n = 1), did not respond to follow-up calls (n = 5), were ill or passed away (n = 1), or were determined to be ineligible (n = 2). CHWs who were categorized as declined (n = 4) missed their interview appointment (n = 2) or did not respond to follow-up calls (n = 2). Of the participating patients, 1 (8%) reported speaking English “very well,” and 8 (62%) reported having less than a high school education. Of the participating CHWs, 12 (80%) self-identified as Hispanic or Latino ethnicity, 9 (60%) self-identified as White race, and 11 (73%) reported speaking Spanish “very well.” The average interview length was 57 minutes (standard deviation [SD] 16) and did not differ between CHW and patient participants.
Table 1.
Patient characteristics
| Characteristic | n = 13 |
|---|---|
| Age (y), mean ± SD | 54.7 ± 7.4 |
| Assigned sex, (n, %) | |
| Female | 7, (53%) |
| Male | 5, 38% |
| Prefer not to say | 1, 8% |
| Woman gender identity (n, %) | 8, 62% |
| Hispanic or Latino ethnicity (n, %) | 13, 100% |
| Race (n, %) | |
| White | 1, 8% |
| Other/prefer not to answer | 12, 92% |
| Marital status (n, %) | |
| Single | 7, 53% |
| Living with partner | 2, 15% |
| Married | 3, 23% |
| Separated | 1, 8% |
| Language proficiency (n, %) | |
| Speaks English “very well” | 1, 8% |
| Speak Spanish “very well” | 9, 69% |
| Country of origin (n, %) | |
| USA | 1, 8% |
| Mexico | 9, 69% |
| Other | 3, 23% |
| Education (n, %) | |
| More than high school | 2, 15% |
| High school or GED | 3, 23% |
| Less than high school | 8, 62% |
| Annual income (n, %) | |
| <$15,000 | 5, 39% |
| $15,00- $24,999 | 6, 46% |
| I do not know | 2, 15% |
| Primary type of insurance (n, %) | |
| Private | 11, 85% |
| Public | 1, 8% |
| I do not know | 1, 8% |
| Employment (n, %) | |
| Full time | 1, 8% |
| Part time | 4, 31% |
| Unemployed | 8, 62% |
| Transportation to dialysis | |
| Private | 11, 85% |
| Public | 2, 15% |
| Time receiving dialysis (years, mean ± SD) | 5.25 ± 2.9 |
| Studies participated in during the last 2 years (median, [IQR])a | (1-1.75) |
| Studies declined during the last 2 years (median, [IQR]) | (0-0) |
Abbreviations: GED, general educational development.
Not including current study.
Table 2.
Community Health Worker Characteristics
| Category | n = 15 |
|---|---|
| Age (y), mean ± SD | 41.7 ± 12.6 |
| Assigned Sex (n, %) | |
| Female | 12, 80% |
| Gender identity (n, %) | |
| Woman | 12,80% |
| Ethnicity (n, %) | |
| Hispanic or Latino | 12, 80% |
| Race (n, %) | |
| White | 9, 60% |
| Other/prefer not to answer | 6, 40% |
| Marital status (n, %) | |
| Single | 6, 40% |
| Living with partner | 2, 33% |
| Married | 5, 33% |
| Language proficiency (n, %) | |
| Speaks English very well | 12, 80% |
| Speak Spanish very well | 11, 73% |
| Country of origin (n, %) | |
| USA | 6, 40% |
| Mexico | 5, 30% |
| Other | 4, 27% |
| Education (n, %) | |
| More than high school | 15, 100% |
| Annual income | |
| 35,000-49,999 | 1, 7% |
| 50,000-74,000 | 9, 60% |
| 75,000-99,999 | 2, 13% |
| 100,000-149,000 | 1, 7% |
| More than 200,000 | 2, 13% |
| Months worked as a community health worker (mean ± SD) | 116 ± 80 |
| Prior health care experience (n, %) | 12, 80% |
| Trained in motivational interviewing (n, %) | 12, 80% |
| Number of studies with Latino individuals in the past 24 months (mean ± SD) | 2.7 ± 2.3 |
We identified 5 themes including 3 facilitators (valuing knowledge and empowerment, building trust between researchers and participants, culturally concordant connection and respect) and 2 barriers (uncertainty and doubt about research, conflicting priorities and burden of participation). The respective subthemes are described below, with supporting quotations reported in Table 3. Fig 1 displays the thematic schema depicting conceptual links across themes.
Table 3.
Themes, Subthemes, and Illustrative Quotes
| Valuing Knowledge and Empowerment | ||
|---|---|---|
| Personal health benefit | It would be for improvement. If they have me for a month to check my weight and see how I react to what they give me to lose weight, I’d be delighted. (Patient 1) | When the parents recognized the benefit that they were going to have for their health, that was something they mentioned a lot …that motivated them a lot to go. (CHW2) |
| There is some benefit from participation …for one's health, which is not good anymore. (Patient 2) | I was really surprised, that it wasn’t so much for the incentive, but for the health benefit, that they were going to have. (CHW2) | |
| All of this also helped me to feel my disease was monitored. (Patient 5) | I just emphasize that the doctors are monitoring really closely. They’re making sure that everything is going okay, and still giving you the baseline medical care that you would have gotten if you weren’t in this study. (CHW4) | |
| Gain knowledge about kidney disease | I would love to continue for my knowledge in general. (Patient 9) | They want to participate because they want to be educated, they want to learn, they want to do this. (CHW3) |
| For me the important thing would be first the information. (Patient 11) | It was always recruiting them in person, talking to them in a friendly way, telling them, “Do you want to know more information about nutrition?” “It’s for your health, but not only for you, for your family, for your children.” (CHW7) | |
| To be able to get well-versed in the health topic. (Patient13) | I think sometimes some people want to participate, because they want to learn the information that we have. (CHW15) | |
| Help the community | If there are things being attempted for the benefit of many people, then it’s worth participating because in the long run, if that works, many people would benefit. (Patient2) | The biggest thing that has helped me get them to respond is by being sincere about the fact that their information is going to help someone. (CHW6) |
| I really like being in research because I love people, I like to love people, see them healthy, see them happy and not go through what I have been through. (Patient4) | Once the interest is mutual, “Okay, I’m interested in improving the health of my community” … I think that helps retain people, because there is that interest beyond the incentive. And they feel more involved like, “Okay, I am part of this, and this is the change that might happen because I am participating.” (CHW13) | |
| It may not be up to me to enjoy the results, but I hope it is up to others. (Patient5) | Always think that they aren’t going to do it for money… the Latino community doesn’t move that way. The Latino community moves if they know the objective, and the benefit they are putting in. (CHW9) | |
| Financial incentives | The incentive has helped me. (Patient6) | Compensation is very important and it’s very important for your recruitment. (CHW5) |
| At the time I had just barely started dialysis and I was getting all my financial stuff ready … it was very helpful. (Patient9) | What does help to retain them… is to give them an incentive, a gift card, something in addition to the classes they are receiving, or the information they receive in a research project. (CHW7) | |
| Many people initially, to be honest, are attracted by the incentive, that they will be paid. (CHW13) | ||
| Building trust between researchers and participants | ||
| Clear communication about the study risks and benefits | [Being] well informed, it’s very important to be well informed. Information on any topic or any information or study, that’s very important, to be well informed to know what you’re doing, what you’re going to receive. (Patient 4) | In the consents there’s always a contact phone number and I always highlight that… Even after you sign the consent, you can withdraw or you can still have questions”, and really making sure that people feel comfortable. (CHW4) |
| That’s the point, they have to explain the pros and cons. (Patient8) | Many studies take time, they take months, so the level of commitment for the Hispanic family, their lives change a lot, it’s very difficult. It’s very difficult sometimes to commit them to see them twice, imagine what it’s like for weeks and months. (CHW12) | |
| Talk to me about the experience we’re going to have. (Patient 4) | [I stress] “This is the research and this is the focus of this project, and this is how it will impact you and this is how it will impact your community in general and why it is necessary to hear from your voice specifically.” (CHW13) | |
| It is also important that they let people know that this or that study is not going to pose risks to them, that builds trust in people. (Patient5) | Being able to explain it and just make it really clear like what they are and are not agreeing to. (CHW15) | |
| Understanding of culture and language | The words in my country are the same as in yours, they don’t mean the same sometimes. (Patient 2) | As soon as the person knows that I’m Hispanic too, you could immediately see that they were happy. And like, “Oh, you know my culture, you know my people.” And then that’s when they’re ready to talk. (CHW2) |
| All Latinos speak Spanish, but for example, Guatemala uses very different words than those used in Mexico …. so it is very difficult for a translator to know all the words they use. (Patient4) | It’s the knowledge you have of how to connect with the Latino. If you know them well enough, or you are one of them, you are going to know, more or less, how to talk to them, it is the tactic, it is the way you understand what research is, so that you maintain that confidence in the Latino you are recruiting. (CHW9) | |
| I don’t like interpreters very much. But of course, it’s a necessity and if there is no other option… but of course one would prefer more in one’s own language. (Patient 13) | As Latinos, we use different words or they are used differently in different countries. So what might sound good in our country is very different elsewhere, even how we compose the same sentence. (CHW11) | |
| Incorporating family support | The whole family gets involved because they have to drop you off, often pick you up, take you to emergencies. It involves a lot for the family, it’s quite draining. But when the family comes together and coordinates, the journey becomes lighter, easier. (Patient 4) | I have patients that don’t know anything about their medical, because they’re older or they don’t speak the language. They recently arrived here in the country so they leave all the decisions to their family. (CHW4) |
| [my family] always supported me. I was always aware of my medications and schedules while participating in the research studies. (Patient 5) | The other thing with this study is we do allow them to bring either a family member or someone with them to the group visit… especially if that person is involved in their health care, then it allows them to have a conversation and have the tools to have that conversation, both of them. (CHW15) | |
| Someone at home could help me read the information. (Patient 12) | [some participants] love spending time with their family but they’re sick and they’re in bed and they can’t do it. So then what I would say is look, when you have the energy and you can do it… it’s going to help you plus your family is going to see. (CHW5) | |
| Culturally concordant connection and respect | ||
| Taking time to build personal connection | They have to be kind, totally kind. (Patient 8) | You know Hispanics well. You have to make a friendship with them through a good greeting, a smile, that’s very important…We have to arrive with the joy of helping the person. Then, they will feel it, they will understand it, they will say, “This person is trustworthy, he wants to help me”. (CHW1) |
| I would like for them to call me first and then go with you and meet. (Patient 11) | Once you are connected, once you connect with the person, once you make the trust, you create trust, then talk about the project, the details, and if they have read a little, they will already know what it is about. Then it will be easier to recruit. (CHW9) | |
| Don’t just come over like, “Oh, I am doing this and this.” No. I want them to say, “Hi, how are you?” And we can open that channel of trust between both of us. (Patient 7) | Building a strong relationship with the person recruiting them… many of the patients I had continued in the study not because of the study itself, but because they had a good relationship with me. (CHW12) | |
| Sincerity and warmth of the connection | It’s more personal, maybe Hispanics like to look people into the eyes to see if they’re really telling the truth or lies, we also want to see if I’m talking to a professional, if I see them hesitating or thinking a lot. (Patient3) | When they already had information that it was something more personal and something they knew, it was like it gave them more confidence to continue listening, and to try to participate. (CHW2) |
| I think that many times Latinos have to have that “second opinion” from someone they trust, right? (Patient 5) | People rightfully have distrust for the medical system. A lot of people have had not so great experiences, especially people in this country that are not White. There’s so much medical racism and xenophobia. Some people are a little weary when it comes to research. Building that trust, and if that comes up in the conversation to not dismiss it, to validate it. (CHW4) | |
| If I don’t connect with them, I won’t do it. (Patient 8) | It was always recruiting them in person, talking to them in a friendly way… creating a connection, creating a connection is the most important thing. (CHW7) | |
| If it doesn’t inspire me trust, then I’m going to say no. But if it inspires me trust, yes, of course, I’m ready. (Patient 4) | The only way is to be honest and committed, to accompany them along the way, and to fulfil what one says. Many times, promises are made and then not kept. As long as one demonstrates from the beginning that one is committed, trust is built with people. (CHW12) | |
| The personal attention that makes the difference and once they feel that connection, “I can talk to this person, I feel comfortable.”, that’s what creates that relationship and trust throughout the study. (CHW13) | ||
| Being involved in the community and having trusted community partners and being visible to the community is really important. (CHW15) | ||
| Approaching with respect and an equal footing | The experience I’ve had in the community and here with dialysis patients is that you have to be very humble, very simple. That they feel, “What a nice person, very humble, very simple.” (Patient 4) | I definitely try and humanize the whole experience…I really try and be personable and humanize. I think when I’m speaking in Spanish, just making sure I’m being really respectful. (CHW4) |
| If they would have emailed me or let me know ahead of time, out of respect, it would have been good. (Patient 9) | Sometimes, they might perceive questions from you as, “Will this person know about these kinds of things?” So, they will be very polite and answer your questions, but there is a certain degree of distrust regarding your qualifications or credentials for being in the position you are in. (CHW11) | |
| Also using a very neutral language so they don’t feel judged, that’s important, not making them feel pressured either. It’s about trying to connect on their level, if the person doesn't have education, you offer politely to read them the papers, to help them, to adapt in any way you can because each person is completely different and cannot be standardized. (CHW12) | ||
| Not judging before understanding why they did something, it’s very important not to judge and also let them know that we are different and to respect that. (CHW12) | ||
| That there are different ways to interact with the community. If you’re going to use your “research hat", and you’re using all these words, it’s like consent, if you read it, they won’t understand you. You have to break it down for people who need you to accommodate that. (CHW13) | ||
| Uncertainty and doubt about the study | ||
| Confusion about research concepts | My question would be, what do I need to do? What method do I have to follow to continue the research? What else can I say? How would it be? I already said that, right? (Patient2) | [Participants ask] “What are the risks? Yeah, and what are the implications? If they get the placebo, what does that mean? Are they not going to get medication? Then you say, “Well, they’ll still get the standard of care.” But that’s just not what people are used to talking about when they’re in the hospital. (CHW4) |
| They are in the hospital, they want to take the advice of doctors. But when it comes to clinical trials or clinical studies, obviously, you have to choose if that’s what you want and you can’t have the team say you consent, you don’t consent or you should do the study, you shouldn’t do the study. It feels like that experience is really new for people to make that decision. (CHW4) | ||
| For me, it was kind of hard because, you go in there, they consent with the hope of getting into the intervention and then they don't get that. (CHW5) | ||
| I think being able to explain it and just make it really clear like what they are and are not agreeing to. (CHW15) | ||
| These are the people that don’t get heard. And my attitude has always been knowledge is power, but only if it’s share. And so how do you share? You let people know what’s going on. (CHW6) | ||
| Discrimination and language barriers | In research studies, Hispanics need to participate, currently, Hispanics are very low in participation, we are just beginning to be invited to participate. (Patient 3) | People rightfully have distrust for the medical system. I think a lot of people have had not so great experiences, especially people in this country that are not white. I think there’s so much medical racism and xenophobia that folks really have had real negative experiences…some people are a little weary when it comes to research. (CHW4) |
| Exactly, we refuse because we don’t know about it, although, I feel that also the research community sometimes pushes us away. (Patient 5) | The word, just the word research, puts them on alert. (CHW9) | |
| Us Mexicans, they don’t want us. They treat the White and Black people better. (Patient 11) | If we see someone well-dressed or well-groomed, we might be influenced to think, “Why is this person participating in research targeting low-income individuals?” (CHW11) | |
| We’re Latinos, but we all have different countries where we come from and we speak differently, so we have to have that sensitivity… I’ve seen a lot of that with interpreters, they don’t understand the word very well. (Patient 2) | lot of times they’ll put patients on hold to get the phone interpreter, but the patients think that they got hung up on because they don’t speak -- they don’t know what that person said, which makes complete sense. (CHW4) | |
| he vocabulary often doesn't match the Spanish translation, so it's much better to have someone who speaks. (Patient 3) | | |
| Conflicting priorities and burden of participation | ||
| Physical impediments precluding participation | It’s not an excuse but it’s practically being with my condition of balance, mobility quite affected. (Patient 2) | With the people that I remember that withdraw from that a lot of times, one of the main reasons I think is they’re too sick, it gets to the point where they’re very ill where they cannot communicate anymore. (CHW5) |
| I couldn’t go anymore because the schedule didn’t allow me to do so, and I also started to feel more and more tired, and it wasn’t easy for me to go there week after week. (Patient 5) | It’s just that things like medical issues come up in their life that they can’t control and don’t have the capacity to participate anymore. (CHW15) | |
| I can’t walk well. (Patient 11) | ||
| Intruding on work priorities | The vast majority of us Latinos, I think, tend to come to this country focused on working hard, without worrying too much about our own health. (Patient 5) | They say, “Well, I think my priorities are to work first and foremost, and to provide for my family. I don't have time to participate in a study, unless it’s going to benefit me, perhaps economically, or perhaps it will help me to have health, or the expectation of a longer life.” (CHW1) |
| We need every day of work. (Patient 5) | That person is going to say, “No, well, I need to know more. Is participating in this study going to prevent me from getting economic benefits? (CHW1) | |
| Because I dedicated myself to work and to work, nothing more. (Patient 4) | Much of the Latino population, either in their home countries or here in the United States, is unfortunately in informal jobs, so schedules are not very flexible. (CHW11) | |
| Lack of transportation and phone communication | I had told them that I felt tired and that it was difficult for me to get around, since I didn’t have a car at that time, I had to ride the bus, so they gave me transportation that time. (Patient5) | Part of the challenge too with our population that we’re working with is transportation to get to, if they have to come in-person to the group visits, then sometimes that's a barrier. We also do work with the clinic to see if we can help either provide transportation in some way. (CHW15) |
| I depend on my husband and my son to take me. They would have to ask for permission at their jobs. (Patient 11) | I would also say if we could offer like bus passes because financially it may also be a challenge, a barrier for them, so if they have that access to transportation, I would say that would also help. (CHW16) | |
| What would prevent me (from participating), maybe the days I go to dialysis, since I don’t drive. (Patient 12) | I feel that for Latino people, call by phone is easier, because of the technology and all that. For example, I feel that my own parents at that age struggle a lot with texting, but I noticed that texting was much better, and they even responded much more when it was through text. (CHW2) | |
Abbreviations: CHW, community health worker.
Figure 1.
Thematic schema. The thematic schema illustrates the relationship between facilitators and barriers and how these can be utilized by CHWs and patients to overcome barriers to participation in clinical research for Latino individuals receiving dialysis. CHWs, community health workers.
Valuing Knowledge and Empowerment
Several motivations for involvement in research were described, including obtaining better health through monitoring or medications offered in the study, gaining knowledge about their disease obtaining financial incentives through patient remuneration. In addition, participants described enrolling to help the kidney disease community as a way of “giving back.”
Personal Health Benefit
Patients were motivated to participate in research if they expected to experience better health as a result. When recruiting Latino patients, CHWs stated that it was important to highlight to patients that participation in research was for their benefit, not for our benefit. (CHW 9, 24 years CHW experience) Patients felt reassured by the constant monitoring of their health during the research follow-up—“all of this helped me to feel my disease was monitored” (Patient 5, 3 years of dialysis). CHWs also found it helpful to emphasize that patients would still receive standard medical care.
Gain Knowledge About Kidney Disease
Patients expressed that they wanted to participate in research to learn more about their health and self-management, such as blood pressure and potassium self-management: “it made me alert to what’s expected if I were to eat too many bananas.” (Patient 9, 6 years of dialysis). CHWs noted that patients “want to participate because they want to be educated.” (CHW 3, 10 years CHW experience)
Help the Community
Participating in research was viewed by patients as an opportunity to bring benefits to the community. “If things are being attempted for the benefit of many people, then it’s worth participating.” (Patient 2, 10 years of dialysis) CHWs recognized this, saying “the fact that their information is going to help someone” can help recruitment (CHW 6, 6 years CHW experience)
Financial Incentives
Both patients and CHWs explained that financial support helped encourage participation as “many times dialysis patients don’t even have enough [money] to pay for a taxi, or to buy pants, or to buy healthy food.” (Patient 4, 2 years of dialysis) CHWs suggested that incentives motivated participant retention: “If you want the second gift card, we need you to finish your participation in the study.” (CHW15, 3 years CHW experience)
Building Trust Between Researchers and Participants
Trust was built between the study participant and researcher through clear communication about the study, including its risks and benefits, and if the researcher was known in the community. Involving the potential participant’s support network and respecting the role family in the Latino communities helped improve trust in the research team.
Clear Communication About the Study Risks and Benefits
For patients, it was important to be well informed about the study, in terms of the study objective, what was involved with participation, what they would receive, and the risks and benefits. Patients valued the opportunity to ask questions and seek further clarification: “The information is obtained through good communication …you want to have the correct information.” (Patient 4, 2 years of dialysis) CHWs stressed the importance of taking the time to explain the study at a literacy level that the patient could understand: “If we want to achieve health equity and truly connect with the people we are going to serve, we need to be able to provide this same type of information consistently to different people, regardless of their level of education.” (CHW 11, 8 years CHW experience)
Understanding of Culture and Language
CHWs described the importance of knowing the community and understanding the community’s needs to build trust and connections when approaching Latino individuals about research: “being involved in the community and having trusted community partners and being visible to the community is really important.” (CHW 15, 3 years CHW experience) Patients noted the importance of cultural concordance: “Hiring Latino people for these types of studies would be very important.” (Patient 6, 5 years of dialysis) Patient participants also noted that research team members who had lived experience with kidney disease may understand more about the disease.
Incorporating Family Support
Participants described the integral role of their families in decision-making about research participation, particularly in terms of providing emotional support, helping understand study information, and providing transportation to study visits. Patients noted: “When the family comes together and coordinates, the journey becomes lighter and easier.” (Patient 4, 2 years of dialysis) Similarly, CHWs noted the importance of this dynamic, commenting: “You might need to speak with not just the one person you're trying to contact but also their family members and be able to explain what's going on to many people who might be involved in their life or their care.” (CHW 15, 3 years CHW experience)
Culturally Concordant Connection and Respect
Participants described that the strength and depth of the connection between the researcher and participant were important to their recruitment and retention. Ways to build connections include taking time, especially face to face; being warm and sincere; and approaching the participant with respect and without an agenda.
Taking Time to Build Personal Connection
Patients described the warmth of the connection and taking time to build a relationship as critical to building trust with researchers. One participant noted, “With us Latinos, we’re used to having a conversation.” (Patient 7, 4 years of dialysis) CHWs noted that face-to-face connection was key to building trust: “People in Latin America love face-to-face contact… they want to feel like they're interacting with a real person.” (CHW 11, 8 years CHW experience)
Sincerity and Warmth of Connection
Both patients and CHWs emphasized that individuals involved in recruiting Latino patients for research had to be sincere, honest, compassionate, and demonstrate a genuine interest in the overall wellbeing of patients. One patient noted, “The sincerity regarding the person who is going to invite you, or honesty, is what matters most.” (Patient 2, 10 years of dialysis) This was particularly important, as some CHWs reported that some patients have “distrust for the medical system [because of] racism. Some people are a little wary when it comes to research.” (CHW 4, 9 years CHW experience)
Approaching With Respect and an Equal Footing
Patients and CHWs discussed that recruiting research teams should avoid arrogance and criticism: “The experience I've had…is that you have to be very humble, very simple.” (Patient 4, 2 years of dialysis) CHWs suggested that individuals recruiting Latino patients should present themselves casually and speak in plain language to allow the participant to feel respected and at ease. One CHW noted, “We look at certain communities as inferior. And I think people realize when that’s happening, and they don't like it.” (CHW 13, 9 years CHW experience)
Uncertainty and Doubt About Research
Certain aspects deterred participants, including lack of clarity on research protocols and utilizing words that participants do not understand. Furthermore, prior discrimination engendered mistrust in research, which was exacerbated by language barriers.
Confusion About Research Concepts
CHWs observed that some patients found it difficult to understand research concepts. For example, CHWs described how randomization can lead to confusion: “You spend a lot of time talking about this potential drug and then you’re like, “And you might not get it.” … that doesn't click with a lot of people.” (CHW 4, 9 years CHW experience) Patients noted they wanted to know about research: “My question would be: what do I need to do? What method do I have to follow to continue the research?” (Patient 7, 4 years of dialysis)
Discrimination and Language Barriers
Some patients perceived that the participation of Latino people in research may be limited due to discrimination: “research community sometimes pushes us away.” (Patient 5, 3 years of dialysis) CHWs similarly remarked that Latino patients may be reluctant to participate because they do not trust the medical system and feel vulnerable due to their undocumented immigration status: “I think rightfully so some people are a little weary when it comes to research.” (CHW 4, 9 years CHW experience) Both patients and CHWs noted how language barriers, including with telephone interpreters, contributed to mistrust and poor communication with potential participants.
Conflicting Priorities and Burden of Participation
Barriers to participation included physical impediments such as pain or fatigue, conflicting work priorities or conflicts with dialysis schedules, and lack of transportation to the study visit.
Physical Impediments Precluding Participation
Poor mobility, fatigue, pain, and ill health were identified by patients and CHWs as barriers to participating in research. CHWs noted: “medical issues come up in their life that they can't control and don't have the capacity to participate anymore.” (CHW15, 3 years CHW experience) One participant noted, “Little by little I got more tired, and it was difficult for me to continue doing it.” (Patient 5, 3 years of dialysis) Many reported that research visits on non-dialysis days were barriers to participation.
Intruding on Work Priorities
Patients explained that work commitments were of high priority among the Latino community: “I dedicated myself to work and to work” (Patient 4, 2 years of dialysis). CHWs noted “there has to be a lot of flexibility” (CHW11, 8 years CHW experience) in work schedules.
Lack of Transportation and Phone Communication
Patients and CHWs identified difficulty with transportation as a key challenge to research participation. Some patients said they would consider participation if they were provided with transportation to study visits: “I could go, if you would have means of transportation to take me.” (Patient 11, 5 years of dialysis) or if research visits were conducted during their usual dialysis sessions. Access to a telephone at home was also identified as a barrier to not only enrollment but also research follow up: “they used these prepaid phones and couldn’t stay in touch after a couple of times.” (CHW12, 13 years CHW experience)
Discussion
In this qualitative study, we found that Latino individuals receiving dialysis in Colorado, were generally interested in participating in research that they perceived as responsive to their individual and community needs, but there are important barriers to their enrollment and retention. Overall, both patients and CHWs emphasized the importance of (1) a trusting relationship grounded in respect, (2) the inclusion of the participant’s caregivers, who are often central to research participation decision-making, and 3) an emphasis on how research contributes to the common good. Developing enrollment strategies focused on building patient-researcher trust will be essential to improving equity in dialysis research participation and health outcomes among the Latino population.
Regarding recruitment strategies, participants described motivations to participate in research as extending beyond individual gains such as improvement of health or knowledge or community good. While this theme has been noted amongst non-Latino individuals receiving dialysis,28 community is particularly important in Latino culture, and many Latino cultures prioritize collectivism (ie, the group over the individual).29,30 Indeed, our prior studies with Latino individuals with kidney disease demonstrated that group connections offer important health benefits,6,7,31,32 and Latino individuals tend to trust and rely upon information transmitted from their community in their medical decision-making. These findings have implications for standard approaches to enrollment for groups who are underrepresented in research. For example, many informed consent forms focus on the benefit to the patient rather than the benefit to the community. Any discussion of broader individual or community benefit would need to be carefully framed in accordance with guidance from the institutional review board to ensure it is informational rather than persuasive and could not be presented in a way that constitutes undue influence or coercion to participate. More broadly, it may be considered whether addressing benefits beyond the individual would be helpful to include for a well-rounded understanding of the effects of research participation.
Identifying strategies to build trust was reported by patients and CHWs as essential to improving research recruitment and retention. Building rapport and trust prior to recruitment, in-person recruitment, calming fear and addressing risk, and personalizing the benefits of participation may enhance participation in research by Latino individuals.33 Personalizing recruitment is critical for Latino communities30- as most CHWs are integrated within the community and are thus inherently trusted, this may be ideal for the minoritized dialysis population.19
Leveraging their established relationships, cultural competence, and community knowledge, CHWs have been successfully incorporated into research efforts in non-Latino populations for research recruitment and retention. Effective strategies include integrating CHWs into community advisory boards, supporting their professional development, and ensuring their contributions are valued and documented. Community engagement with researchers is critical to establish trust; in one survey, Black Americans reported increased motivation to participate in trials if the research team was engaged with the participants.34 One example of a successful community-engaged research program prioritizing recruitment and retention of underrepresented populations is the Fostering African-American Improvement in Total Health program.35 This program utilized a community steering committee, which included local community leaders and academic researchers. The success of this program was based on the equal partnership of community and academic medicine allowing for 2-way communication and sharing of values.35 More broadly, these approaches have been shown to promote equitable partnerships, enhance recruitment of underrepresented populations, and improve the overall quality and impact of research.36
Unsurprisingly, we also found that language barriers can limit research recruitment. Latino people with limited English proficiency experience persistent communication barriers, even when interpreter services are available, due to overlapping challenges related to cultural traditions, immigration status, and socioeconomic needs.6 These factors contribute to mistrust and poorer health outcomes and are thus less likely to be mitigated by interpreters alone. Furthermore, many clinical trials exclude non-English speakers, further limiting the representativeness of the sample population. This also means participants who do not speak English are excluded from important, clinically relevant trials without knowledge of their exclusion. Given the data supporting use of CHWs in English speaking studies, language and culturally concordant CHWs could be one solution to bridge this gap.
Finally, structural barriers play an important role for patients treated with dialysis in study retention. Many interviewees reported dependency on family for transportation to dialysis, preferring that research visits occur on dialysis days when they had prearranged transportation. Many Latino patients, especially those whose immigration status preclude disability benefits, described working on non-dialysis days. Flexibility in research design, including study visit timing and location, is critical for equitable participation. This may entail working with dialysis units to accommodate researchers in the dialysis unit to ensure flexibility is balanced with patient privacy and safety.
Our study has limitations. First, we interviewed people who had some experience with research- the perspective of those patients who do not engage in research is still unknown. We enrolled participants from 2 dialysis units in a single city, and CHWs were all local to Colorado, limiting transferability to a wider population. We did not elicit information on the types of clinical trials interviewees had participated in, which also limits transferability. While we did not document immigration status, some barriers faced by participants in our study may be unique to the undocumented population, and these findings may not be transferable to other populations. Furthermore, most of the participants reported limited English proficiency. While the majority (two-thirds) of Latino patients with kidney disease have limited English proficiency, this may not be transferable to English-proficient Latino individuals.37 Future research including Latino people who have chosen not to participate in research is critical to fully understanding the barriers to research participation for this population.
In summary, we found a trusting relationship and understanding of the potential participant’s needs and motivations to engage in research as key facilitators to dialysis research participation among Latino individuals receiving dialysis, a key demographic underrepresented in dialysis research. Insights from this study will inform the development of strategies aimed at improving the participation and retention of Latino individuals in dialysis research.
Article Information
Authors’ Full Names and Academic Degrees
Katherine Rizzolo, MD, Jennifer E. Flythe, MD, MPH, Claudia Camacho, BA, Andrea Matus Gonzalez, PhD, Allison Jaure, PhD, Sanjna Vinze, MD, and Lilia Cervantes, MD, MSCS
Authors’ Contributions
Research area and study design: JF and CL, data acquisition: CC and CL; data analysis and interpretation: KR, AJ, AMG, and SV; statistical analysis: KR and AJ; supervision or mentorship: JF and CL. Each author contributed important intellectual content during manuscript drafting or revision and accepts accountability for the overall work by ensuring that questions pertaining to the accuracy or integrity of any portion of the work are appropriately investigated and resolved.
Support
Research reported in this work was funded through a Patient-Centered Outcomes Research Institute (PCORI) Award (IHS-2021C2-23534). The views in this work are solely the responsibility of the authors and do not necessarily represent the views of the PCORI, its Board of Governors or Methodology Committee.
Financial Disclosure
Dr Flythe reports receiving consulting fees from Aquapass and Fresenius Medical Care. The other authors declare that they have no relevant financial interests.
Peer Review
Received September 21, 2025. Evaluated by 2 external peer reviewers, with direct editorial input from an Associate Editor and the Editor-in-Chief. Accepted in revised form December 29, 2025.
Footnotes
Complete author and article information provided before references.
Item S1: Interview Guide for Patient Participants.
Item S2: Interview Guide for Community Health Work Participants.
Supplementary Material
Items S1-S2,
References
- 1.Centers for Medicare & Medicaid Services End Stage Renal Disease Medical Evidence Report: Medicare Entitlement and/or Patient Registration (CMS-2728) Revised June 1, 2025. OMB No. 0938-0046. https://www.cms.gov/medicare/cms-forms/cms-forms/downloads/cms2728.pdf
- 2.Zarkowsky D.S., Arhuidese I.J., Hicks C.W., et al. Racial/ethnic disparities associated with initial hemodialysis access. JAMA Surg. 2015;150(6):529–536. doi: 10.1001/jamasurg.2015.0287. [DOI] [PubMed] [Google Scholar]
- 3.Purnell T.S., Luo X., Cooper L.A., et al. Association of race and ethnicity with live donor kidney transplantation in the United States from 1995 to 2014. JAMA. 2018;319(1):49–61. doi: 10.1001/jama.2017.19152. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Shen J.I., Chen L., Vangala S., et al. Socioeconomic factors and racial and ethnic differences in the initiation of home dialysis. Kidney Med. 2020;2(2):105–115. doi: 10.1016/j.xkme.2019.11.006. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Cervantes L., Sinclair M., Camacho C., Santana C., Novick T., Cukor D. Social and behavioral barriers to effective care during the transition to end-stage kidney care. Adv Kidney Dis Health. 2024;31(1):21–27. doi: 10.1053/j.akdh.2023.09.005. [DOI] [PubMed] [Google Scholar]
- 6.Cervantes L., Rizzolo K., Carr A.L., et al. Social and cultural challenges in caring for latinx individuals with kidney failure in urban settings. JAMA Netw Open. 2021;4(9) doi: 10.1001/jamanetworkopen.2021.25838. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Rizzolo K., Gonzalez Jauregui R., Barrientos I., et al. Barriers and facilitators to home dialysis among latinx patients with kidney disease. JAMA Netw Open. 2023;6(8) doi: 10.1001/jamanetworkopen.2023.28944. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Pereira R.I., Cervantes L. Reducing the burden of CKD among latinx: A community-based approach. Clin J Am Soc Nephrol. 2021;16(5):812–814. doi: 10.2215/CJN.12890820. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Novick T.K., Barrios F., Osuna M., et al. Facilitating medical care for latinx individuals at risk for CKD: A pilot intervention. Kidney Med. 2023;5(8) doi: 10.1016/j.xkme.2023.100679. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 10.Soomro Q.H., McCarthy A., Varela D., et al. Representation of racial and ethnic minorities in nephrology clinical trials: A systematic review and meta-analysis. J Am Soc Nephrol. 2023;34(7):1167–1177. doi: 10.1681/ASN.0000000000000134. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 11.Wendler D., Kington R., Madans J., et al. Are racial and ethnic minorities less willing to participate in health research? PLOS Med. 2006;3(2) doi: 10.1371/journal.pmed.0030019. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12.Reopell L., Nolan T.S., Gray D.M., II, et al. Community engagement and clinical trial diversity: navigating barriers and co-designing solutions-A report from the “Health Equity through Diversity” seminar series. PLOS One. 2023;18(2) doi: 10.1371/journal.pone.0281940. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 13.Garza M.A., Li Y., Fryer C.S., et al. Bridging the gap: understanding Latino willingness to participate in public health and clinical trials research across diverse subgroups. Contemp Clin Trials Commun. 2025;44 doi: 10.1016/j.conctc.2025.101440. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 14.Clark L.T., Watkins L., Piña I.L., et al. Increasing diversity in clinical trials: overcoming critical barriers. Curr Probl Cardiol. 2019;44(5):148–172. doi: 10.1016/j.cpcardiol.2018.11.002. [DOI] [PubMed] [Google Scholar]
- 15.Kahn J.M., Gray D.M., II, Oliveri J.M., Washington C.M., DeGraffinreid C.R., Paskett E.D. Strategies to improve diversity, equity, and inclusion in clinical trials. Cancer. 2022;128(2):216–221. doi: 10.1002/cncr.33905. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16.Regnante J.M., Richie N.A., Fashoyin-Aje L., et al. US cancer centers of excellence strategies for increased inclusion of racial and ethnic minorities in clinical trials. J Oncol Pract. 2019;15(4):e289–e299. doi: 10.1200/JOP.18.00638. [DOI] [PubMed] [Google Scholar]
- 17.Alarcón Garavito G.A., Gilchrist K., Ciurtin C., et al. Enablers and barriers of clinical trial participation in adult patients from minority ethnic groups: a systematic review. Trials. 2025;26(1):65. doi: 10.1186/s13063-025-08769-y. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 18.Alvarado F., Delgado C., Nicholas S.B., Jaure A., Cervantes L. Qualitative analysis of stakeholder perspectives on engaging Latinx patients in kidney-related research. BMC Nephrol. 2023;24(1):79. doi: 10.1186/s12882-023-03128-y. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19.Killough C.M., Madaras A., Phillips C., et al. Community health worker insights on promoting research engagement with diverse populations. Front Public Health. 2022;10 doi: 10.3389/fpubh.2022.959504. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 20.Cervantes L., Robinson B.M., Steiner J.F., Myaskovsky L. Culturally Concordant Community-Health workers: building sustainable community-based interventions that eliminate kidney health disparities. J Am Soc Nephrol. 2022;33(7):1252–1254. doi: 10.1681/ASN.2022030319. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21.Tong A., Sainsbury P., Craig J. Consolidated criteria for reporting qualitative research (COREQ): a 32-item checklist for interviews and focus groups. Int J Qual Health Care. 2007;19(6):349–357. doi: 10.1093/intqhc/mzm042. [DOI] [PubMed] [Google Scholar]
- 22.Rizzolo K., Cervantes L. Barriers and solutions to kidney transplantation for the undocumented latinx community with kidney failure. Clin J Am Soc Nephrol. 2021;16(10):1587–1589. doi: 10.2215/CJN.03900321. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 23.Guest G., Bunce A., Johnson L. How many interviews are enough?: an experiment with data saturation and variability. Field Methods. 2006;18(1):59–82. doi: 10.1177/1525822X05279903. [DOI] [Google Scholar]
- 24.Bowen G.A. Grounded theory and sensitizing concepts. Int J Qual Methods. 2006;5(3):12–23. doi: 10.1177/160940690600500304. [DOI] [Google Scholar]
- 25.Corbin J.M., Strauss A. Grounded theory research: procedures, canons, and evaluative criteria. Qual Sociol. 1990;13(1):3–21. doi: 10.1007/BF00988593. [DOI] [Google Scholar]
- 26.Glaser B., Strauss A.L. Aldine Transaction; 1967. The Discovery of Grounded Theory: Strategies for Qualitative Research. [Google Scholar]
- 27.Hennick M, Hi BA. Qualitative Research Methods. Sage Publications.
- 28.Flythe J.E., Narendra J.H., Dorough A., et al. Perspectives on research participation and facilitation among dialysis patients, clinic personnel, and medical providers: A focus group study. Am J Kidney Dis. 2018;72(1):93–103. doi: 10.1053/j.ajkd.2017.10.011. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 29.Caballero A.E. Understanding the Hispanic/Latino patient. Am J Med. 2011;124(10 suppl):S10–S15. doi: 10.1016/j.amjmed.2011.07.018. [DOI] [PubMed] [Google Scholar]
- 30.García A.A., Zuñiga J.A., Lagon C. A personal touch: the most important strategy for recruiting Latino research participants. J Transcult Nurs. 2017;28(4):342–347. doi: 10.1177/1043659616644958. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 31.Rizzolo K., Gardner C., Camacho C., et al. In-center hemodialysis experiences among latinx adults: a qualitative study. Kidney Med. 2024;6(11) doi: 10.1016/j.xkme.2024.100902. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 32.Rizzolo K., Rockey N., Camacho C., Gardner C., Giusti S., Cervantes L. The transplant experience for undocumented immigrant patients formerly receiving emergency dialysis and caregivers. JAMA Netw Open. 2024;7(2) doi: 10.1001/jamanetworkopen.2023.54602. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 33.Sha M., McAvinchey G., Quiroz R., Moncada J. Successful techniques to recruit Hispanic and Latino research participants. Surv Pract. 2017;10(3):1–9. doi: 10.29115/SP-2017-0014. [DOI] [Google Scholar]
- 34.Manjunath C., Ifelayo O., Jones C., et al. Addressing cardiovascular health disparities in Minnesota: establishment of a community steering committee by Faith! (Fostering African-American Improvement in Total Health) Int J Environ Res Public Health. 2019;16(21):4144. doi: 10.3390/ijerph16214144. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 35.Kanaya A.M., Kandula N., Herrington D., et al. Mediators of Atherosclerosis in South Asians Living in America (MASALA) study: objectives, methods, and cohort description. Clin Cardiol. 2013;36(12):713–720. doi: 10.1002/clc.22219. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 36.Di Muro F.M., Dangas K., Ortega R., et al. Preserving and promoting clinical trial representativeness: a review of existing strategies and the path forward. JAMA Cardiol. 2025;10(9):954–960. doi: 10.1001/jamacardio.2025.2421. [DOI] [PubMed] [Google Scholar]
- 37.Fischer M.J., Go A.S., Lora C.M., et al. CKD in Hispanics: baseline characteristics from the CRIC (Chronic Renal Insufficiency Cohort) and Hispanic-CRIC Studies. Am J Kidney Dis. 2011;58(2):214–227. doi: 10.1053/j.ajkd.2011.05.010. [DOI] [PMC free article] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Items S1-S2,