Abstract
Background:
Africa faces a growing burden of cancer yet remains underrepresented in global cancer clinical trials. This disparity limits the generation of population-specific evidence needed to improve cancer outcomes. Recruitment and retention in cancer clinical trials are particularly challenging due to various systemic and individual barriers in Nigeria. This study explores patients’ perspectives on barriers and facilitators to recruitment and retention in cancer clinical trials.
Methods:
A convergent parallel mixed-methods design was employed, comprised of a cross-sectional survey and descriptive qualitative approach. Participants were recruited from multiple oncology centers and secondary facilities within Nigeria’s ICON-3 Practice-Based Research Network. Quantitative data were collected through interviewer-administered questionnaires, while qualitative data were gathered via semi-structured interviews and analyzed thematically.
Results:
A total of 317 patients participated in the quantitative survey, 18 of whom participated in interviews. Barriers included limited understanding of clinical trials, logistical challenges such as transportation and visit frequency, distrust in researchers and the healthcare system, and lack of family support. Facilitators included effective communication, incentives, flexible research visits, and culturally tailored interventions.
Conclusion:
To optimize cancer clinical trial participation in low-resource settings, interventions must be tailored to local contexts, addressing structural and cultural barriers. Enhanced communication, community involvement, and supportive policies can significantly improve trial participation and outcomes.
Keywords: Cancer clinical trials, recruitment, retention, patients’ perspectives, low-resource settings, Africa, cancer, clinical trials, participation
INTRODUCTION
Africa has a growing burden of cancer, with new cases and cancer deaths projected to increase by 135% and 142%, respectively from 2022 to 2050.(1) However, African countries are poorly represented in cancer clinical trials,(2) comprising only 1.8% of the 106,023 trials listed on ClinicalTrials.gov as of June 2024. This disparity highlights the dearth of population-specific evidence to improve cancer outcomes.
The limited inclusion of African countries has been attributed to weak infrastructure, concerns about research integrity and ethics, limited skilled professionals, and poor participant accrual. (3,4) While data from Africa is sparse, estimates from other regions indicate that about half of cancer patients participate in clinical trials when offered (5) and approximately 20% of cancer clinical trials fail due to insufficient patient enrollment.(6) Studies have identified barriers to participation of racial minorities in cancer clinical trials, including patient, provider, trial, and systems-related barriers. (7–12) Structural and trial-related factors are the leading barriers affecting participant accrual in high-income countries.(13)
To improve participation in cancer clinical trials in Africa, further insight into context-specific barriers and facilitators to recruitment and retention are needed from both the provider and patient perspectives. Thus, our group evaluated barriers and facilitators to participation in cancer clinical trials in Nigeria in both providers (14) and patients. This paper reports specifically on the barriers and facilitators to clinical trial participation from the patients’ perspectives.
METHODS
Study Design and Setting
A convergent parallel mixed-methods design was employed, with equal priority given to quantitative and qualitative data. The study was conducted between December 2023 and February 2024 within the ICON-3 Practice-Based Research Network (PBRN), established by the IVAN Research Institute in Nigeria. Ethical approval was obtained from the Nigerian National Health Research Committee (NHREC/01/01/2007–14/03/2023) and the Johns Hopkins Institutional Review Board.
Study Population and Recruitment
For the quantitative survey, adult patients receiving care at six Regional Oncology Centers of Excellence and 12 Nigeria Implementation Science Alliance, Model Innovation and Research Centers (NISA-MIRCs) were recruited using convenience and purposive sampling. A total of 330 participants were approached, of whom 317 provided consent and participated while 13 declined to take part. For the qualitative study, purposive sampling was used to recruit 18 participants from the same facilities.
Data collection
Quantitative data were collected using a newly developed pretested, interviewer-administered questionnaires. The questionnaire included three sections: (1) Background information, (2) Barriers to participation including knowledge and understanding of clinical trials, study burden, distrust of researchers, beliefs/culture, nature of trials, and fear of randomization, (3) Facilitators of participation including incentives, flexible research visits, effective communication, attitudes of research staff, and cultural competence. Barriers and facilitators were assessed using a five-point Likert scale (ranging from “very unlikely” to “very likely”).
The qualitative phase used a semi-structured interview guide based on the socioecological framework. The face-to-face interviews were audio-recorded and transcribed verbatim. Field notes documented non-verbal cues and contextual factors.
Data Analysis
Quantitative data were analyzed using descriptive statistics, including percentages. Qualitative data analysis involved thematic analysis using NVivo software. A codebook was developed, with additional codes emerging inductively. Themes and subthemes were organized into nodes, providing a visual and systematic representation of the data. Representative quotes from the in-depth interviews are provided, below, to exemplify the themes and subthemes. We compared emerging themes with statistical trends and triangulated the data using a concordant approach.
RESULTS
A total of 317 patients participated in the quantitative survey, 18 of whom also participated in interviews (Table 1).
Table 1:
Characteristics of study participants
| Characteristics | Entire population N=317 except where otherwise stated (%) | Qualitative cohort N=18 (%) |
|---|---|---|
|
Sex Male Female |
138 (43.5) 179 (65.5) |
8 10 |
|
Education
level None Completed primary school Completed junior secondary Completed senior secondary Completed post-senior secondary |
24 (7.6) 30 (9.5) 12 (3.8) 103 (32.5) 148 (46.7) |
0 0 0 7 11 |
|
Marital
status Married Living with a partner Single Divorced Widowed |
209 (65.9) 3 (0.9) 60 (18.9) 16 (5.0) 29 (9.1) |
11 0 4 1 2 |
|
Religion Christian Islam Traditional |
226 (71.3) 90 (28.4) 1 (0.3) |
14 4 0 |
|
Area of
residence Rural Semi-urban Urban |
66 (20.8) 103 (32.5) 148 (46.7) |
8 3 7 |
|
Ethnicity Yoruba Igbo Hausa Others |
45 (14.2) 72 (22/7) 64 (20.2) 136 (42.9)( |
N/A N/A N/A N/A |
|
Occupation Student Unemployed Artisan Trader Businessman/woman Civil servant |
21 (6.6) 38 (12.0) 21 (6.6) 64 (20/2) 91 (28.7) 82 (25.9) |
1 3 2 2 4 6 |
|
Diagnosed with
cancer Yes No Not sure |
83 (26.2) 231 (72.9) 3 (0.9) |
N/A N/A N/A |
|
Family member diagnosed with
cancer Yes No Not sure |
77 (24.4) 217 (68.7) 22 (7.0) |
N/A N/A N/A |
|
Participated in clinical
trial Yes No Not sure |
19 (6.0) 291 (92.1) 6 (1.9) |
N/A N/A N/A |
|
Participated in cancer clinical trial
(N=9) Yes No Not sure |
4 (21.1) 15 (78.9) 0 |
N/A N/A N/A |
|
Know someone who participated in
clinical
trials Yes No Not sure |
22 (6.9) 266 (83.9) 29 (9.1) |
N/A N/A N/A |
|
Know someone who participated in cancer
clinical trials
(N=22) Yes No Not sure |
7 (31.8) 9 (40.9) 6 (27.3) |
N/A N/A N/A |
Patient-Related Barriers to participation in cancer clinical trials
Knowledge and understanding of cancer clinical trials
Over 50% of the participants reported that not understanding the clinical trial process (69%), not understanding the need for the clinical trial (60%), not understanding medical language in trials (61%), and not understanding the research problem (56%) were “likely” or “very likely” to prevent participation in a cancer clinical trial. (Table 2).
Table 2.
Barriers to participation in cancer clinical trials
| Very Unlikely N (%) | Unlikely N (%) | Neutral N (%) | Likely N (%) | Very Likely N (%) | |
|---|---|---|---|---|---|
| Knowledge and understanding of cancer clinical trial | |||||
| Not understanding the clinical trial process | 40 (12.6) | 28 (8.8) | 31 (9.8) | 116 (36.6) | 102 (32.2) |
| Not understanding the need for the clinical trial | 42 (13.2) | 49 (15.5) | 36 (11.4) | 129 (40.7) | 61 (19.2) |
| Not understanding medical language in trials | 36 (11.4) | 48 (15.1) | 42 (13.2) | 107 (33.8) | 84 (26.5) |
| Not understanding the research problem | 42 (13.2) | 53 (16.7) | 46 (14.5) | 107 (33.8) | 69 (21.8) |
| Recruiter not fluent in my language | 69 (21.8) | 64 (20.2) | 40 (12.6) | 72 (22.7) | 72 (22.7) |
| Study burden | |||||
| Transportation will be a problem for me | 34 (10.7) | 29 (9.1) | 24 (7.6) | 97 (30.6) | 133 (42.0) |
| Number of visits to the hospital for the trial | 21 (6.6) | 35 (11.0) | 21 (6.6) | 118 (37.2) | 122 (38.5) |
| No incentive for participation | 23 (7.3) | 40 (12.6) | 47 (14.8) | 116 (36.6) | 91 (28.7) |
| Nobody to look after my family | 51 (16.1) | 82 (25.9) | 46 (14.5) | 66 (20.8) | 72 (22.7) |
| Hard to take time away from work | 37 (11.7) | 68 (21.5) | 44 (13.9) | 95 (30.0) | 73 (23.0) |
| Long consent process | 33 (10.4) | 50 (15.8) | 60 (18.9) | 112 (35.3) | 62 (19.6) |
| Hospital/clinic is not in a convenient location | 41 (12.9) | 68 (21.5) | 52 (16.4) | 76 (24.0) | 80 (25.2) |
| Distrust of researcher | |||||
| No trust in the people approaching me | 67 (21.1) | 55 (17.4) | 41 (12.9) | 92 (29.0) | 62 (19.6) |
| Researchers are not from my culture | 83 (26.2) | 83 (26.2) | 52 (16.4) | 60 (18.9) | 39 (12.3) |
| No trust in clinical trials in general | 62 (19.6) | 70 (22.1) | 63 (19.9) | 73 (23.0) | 49 (15.5) |
| Belief/culture | |||||
| Lack of partner/family consent | 72 (22.8) | 59 (18.7) | 50 (15.8) | 81 (25.6) | 54 (17.1) |
| Belief against human participation in trials | 89 (28.1) | 70 (22.1) | 73 (23.0) | 45 (14.2) | 40 (12.6) |
| Religion frowns against participating | 128 (40.4) | 74 (23.3) | 50 (15.8) | 39 (12.3) | 26 (8.2) |
| Culture frowns against participating | 116 (36.6) | 85 (26.8) | 57 (18.0) | 39 (12.3) | 20 (6.3%) |
| Past negative experiences with experiments | 110 (34.7) | 72 (22.7) | 84 (26.5) | 35 (11.0) | 16 (5.0) |
| Nature of clinical trial | |||||
| Invasive procedures (Injections, Imaging) | 57 (18.0) | 36 (11.4) | 26 (8.2) | 93 (29.4) | 104 (32.9) |
| Taking tablets or syrups | 56 (17.7) | 70 (22.1) | 26 (8.2) | 83 (26.2) | 82 (25.9) |
| Sharing personal and medical data | 71 (22.4) | 85 (26.8) | 47 (14.8) | 67 (21.1) | 47 (14.8) |
| Collecting samples (e.g., blood, tissue) | 56 (17.7) | 63 (19.9) | 30 (9.5) | 64 (20.3) | 103 (32.6) |
| Fear or risk of randomization | |||||
| Fear of negative effects/side effects | 38 (12.0) | 45 (14.2) | 40 (12.6) | 107 (33.8) | 87 (27.4) |
| Feeling like a “Guinea Pig” | 84 (26.6) | 56 (17.7) | 46 (14.6) | 75 (23.7) | 55 (17.4) |
| Fear of loss of control over health decisions | 50 (15.8) | 70 (22.1) | 66 (20.8) | 93 (29.3) | 38 (12.0) |
| Fear of being in a group that does not receive treatment | 54 (17.1) | 70 (22.2) | 75 (23.7) | 92 (29.1) | 25 (7.9) |
| Fear of disclosure of illness/disease due to participation | 70 (22.2) | 77 (24.4) | 60 (19.0) | 76 (24.1) | 33 (10.4) |
In qualitative interviews, effective communication was emphasized as a fundamental element in the decision-making process for clinical trial participation.
“… communication can affect participation in that, complete and correct information on processes, reason and duration is essential to their participation. That is, if they understand the basics of the study.” 1
Thus, transparent communication of what the trial entails impacts patients’ decision to engage. Moreover, participants emphasized the importance of simplifying complex medical information,
“I believe communication should be done in the simplest of terms, in the language of the participants and frequently to encourage and keep interest.” 2
This indicates that using native language, uncomplicated language and frequent communication can help bridge the understanding gap and maintain participants’ engagement. Transparent communication and use of simple language were emphasized.
“… communicating in a language they do not understand will affect their participation negatively.” 3
Study burden
Over 70% of the participants reported that transportation issues (73%) and the number of visits to the hospital (76%) would likely or very likely prevent their participation in a cancer clinical trial. More than half of participants also reported that lack of incentive (65%), a long consent process (55%), and difficulty in taking time away from work (53%) would likely or very likely prevent their participation (Table 2).
Similarly, in the interviews, the distance to healthcare facilities and transportation issues were noted to be prominent barriers.
“I mean maybe they might be needed to come to the facility for one thing or the other, so at that point they might say they don’t [have] transport to come at that time.”4
Logistical challenges posed by frequent trips to healthcare facilities were also identified as a concern.
“Also, timing, if they have to be coming to the facility all the time, it might affect their participation because of the cost of transportation and the distance.” 5
Distrust of Researcher
Nearly half of the respondents (49%) reported that lack of trust in the individuals approaching them about clinical trials will likely or very likely prevent them from participating in cancer clinical trials. Only about a third responded that the research not being from their culture (31%) or lack of trust in clinical trials (39%) were likely or very likely to limit their participation in a cancer clinical trial.
In the qualitative interviews, participants did emphasize trust as a critical determinant.
“First, if I do not trust the health facility and secondly if I do not trust the health care providers.” 6
Participants also expressed that insufficient and inadequately trained staff can be a barrier to participation.
“There is shortage of staff everywhere. We have more volunteers than staff doing the most.”7 The role of poor health infrastructure, such as unavailable equipment, also emerged as a critical determinant of trial participation.
“Poor infrastructure causes fear in participants. The government and other organizations should help in this aspect to give us better infrastructure.” 8
“When people come in and see an unequipped place they will not feel comfortable to participate in trials.” 9
These comments underscore the relevance of healthcare providers and the environment in fostering trust, comfort, and engagement in the trial process.
Family support
Only 27% of participants noted that their belief against human participation in trials was likely or very likely to prevent them from participating, and less than a quarter of participants reported that religious (21%) or cultural stance (19%), or past negative experiences were (16%) were likely or very likely to prevent them from participation. However, lack of partner/family consent was more commonly identified (43% likely or very likely) as a barrier (Table 2).
In the qualitative analysis, the influences of family support did prevail as a significant theme. Participants expressed the importance of family and the impact of the spouse in decision making.
“Of sure, family can. If they aren’t supportive, you may retreat. Yes, he [spouse] is one of the major inspirations. If he says don’t do it, I won’t; if he says yes, I will.” 10
Fear and Nature of cancer clinical trials
Over 50% of the respondents identified fear of negative effects/side effects (61%), invasive procedures (62%), collecting samples (53%), or taking tablets or syrups (52%) as barriers to participation in a cancer clinical trial (Table 2).
Similar concerns were expressed in the qualitative interviews.
“Honestly, the fear of injection or taking drugs that you’re not sure of the effect on you. The outcome may be negative and even be death.” 11
“At times such drugs may lead to the death of the patients because they don’t know what they are taking.” 12
“In Nigeria, people are scared if the drug trial will be harmful to them.” 13
Fear of cancer clinical trial may stem from the community and may be based on myths and misconceptions.
Definitely, community perceptions will hinder people from participating because of how rumors fly in the communities.” 14
“I have a friend, after taking the COVID vaccine, he slumped and later died. So sometimes it scares people away from doing clinical trials.” 15
Thus, fear of harm or even death was noted to be a significant barrier to clinical trial participation.
Facilitators of participation in cancer clinical trials
Flexible Research Visits and Incentives
Providing transportation costs (79%) or other incentives (75%), reimbursement of out-of-pocket expenses (78%), online/phone interviews (64%), home visits (62%), not having too many study visits (77%), and the trial adjusting to unforeseen scheduling conflicts (72%) were identified as strong facilitators (Table 3).
Table 3.
Facilitators of participation in cancer clinical trials
| Very Unlikely N (%) | Unlikely N (%) | Neutral N (%) | Likely N (%) | Very Likely N (%) | |
|---|---|---|---|---|---|
| Incentives | |||||
| Participation if given incentives | 12 (3.8) | 20 (6.3) | 46 (14.5) | 78 (24.6) | 161 (50.8) |
| Participation if transportation cost is covered | 4 (1.3) | 20 (6.3) | 43 (13.6) | 81 (25.6) | 169 (53.3) |
| Participation if reimbursed for out-of-pocket expenses | 9 (2.8) | 16 (5.0) | 46 (14.5) | 79 (24.9) | 167 (52.7) |
| Flexible research visits | |||||
| Participation if study visits are not too many | 9 (2.8) | 17 (5.4) | 47 (14.8) | 130 (41.0) | 114 (36.0) |
| Participation if some visits are online/phone interviews | 12 (3.8) | 22 (6.9) | 79 (24.9) | 104 (32.8) | 100 (31.5) |
| Participation if home assessment is possible | 21 (6.6) | 20 (6.3) | 80 (25.2) | 103 (32.5) | 93 (29.3) |
| Participation if trial can adjust to unforeseen scheduling conflicts | 10 (3.2) | 16 (5.0) | 62 (19.6) | 126 (39.7) | 103 (32.5) |
| Effective communication | |||||
| Participation if trial is explained in a language understood | 4 (1.3) | 10 (3.2) | 35 (11.0) | 103 (32.5) | 165 (52.1) |
| Participation if informed about risks, benefits, and randomization | 6 (1.9) | 13 (4.1) | 38 (12.0) | 116 (36.6) | 144 (45.4) |
| Participation if research team keeps in regular touch | 8 (2.5) | 6 (1.9) | 53 (16.7) | 112 (35.3) | 138 (43.5) |
| Attitude of research staff/team | |||||
| Participation if recruiting staff attitude is good | 4 (1.3) | 9 (2.8) | 22 (7.0) | 105 (33.2) | 176 (55.7) |
| Participation if research team treats with respect | 5 (1.6) | 10 (3.2) | 25 (7.9) | 97 (30.6) | 180 (56.8) |
| Participation if research team can communicate properly | 4 (1.3) | 7 (2.2) | 27 (8.6) | 105 (33.4) | 171 (54.5) |
| Address cultural competence | |||||
| Participation if research team considers my culture | 24 (7.6) | 26 (8.2) | 75 (23.7) | 114 (36.0) | 78 (24.6) |
| Participation if materials are culturally tailored | 24 (7.6) | 22 (6.9) | 82 (25.9) | 126 (39.7) | 63 (19.9) |
| Participation if at least one team member is from my place | 35 (11.0) | 33 (10.4) | 109 (34.4) | 83 (26.2) | 57 (18.0) |
| Participation if community leader approves of the clinical trial | 68 (21.5) | 29 (9.1) | 89 (28.1) | 79 (24.9) | 52 (16.4) |
| Participation if religious leader approves of the clinical trial | 55 (17.4) | 31 (9.8) | 81 (25.6) | 92 (29.1) | 57 (18.0) |
| Participation if partner/family approves of the clinical trial | 38 (12.1) | 19 (6.0) | 55 (17.5) | 103 (32.7) | 100 (31.7) |
The qualitative interviews similarly suggested that providing tangible or intangible incentives motivates recruitment and long-term retention.
“Yes, if incentives are involved, I think it will motivate participation. If people see that there is something that they can benefit from it, it will motivate participation”.16
“Incentives are what we always look out for first. With these in place, everything will be easy.” 17
Effective communication
The use of effective communication strategies to build trust was also an important theme.
Clear explanations (explaining the trial in a language they understand (85%), frequent communication (providing information about risks, benefits, and randomization (82%), the research team keeping in regular touch (79%), and use of participant’s native language were reported as critical (Table 3).
“Yes, using a common indigenous language in the community will make people feel safer and more willing to participate. It will also be easy and you won’t have to say many things for you to be understood13
“Patient education is important because it has to do with educating, sensitizing and preparing the participants for the study. Posters and flyers are good tools for patient education”.18
Thus, having a common language and being able to adequately educate participants are both important to facilitating participation.
Attitude of research staff/team
Most participants responded that the good attitude of recruiting staff and proper communication (89% for both) and treating participants with respect (87%) facilitate participation in cancer clinical trials (Table 3).
In the qualitative analysis, empathy, professionalism, clear communication, and confidentiality were valued by participants.
“If those health workers can have those good qualities; mode of communication, confidentiality, it will really influence and make more people to participate.”19
Thus, a key factor in participants’ willingness to engage in clinical trials was the perceived attitude of healthcare workers, particularly in terms of communication style and professionalism.
Cultural competence
Some aspects of cultural competence were identified to be important facilitators of participation, including approval of the clinical trial by a partner/family (64%), the research team considering a participant’s culture (61%) and materials being culturally tailored (60%). Other factors were less likely to be important facilitators including at least one team member is from my place (44%), a community leader approving of the clinical trial (41%), and approval of the clinical trial by a religious leader (47%) (Table 3).
In the interviews, participants highlighted the importance of meaningful involvement of communities in trial design and implementation. Active engagement promotes a sense of shared ownership in health initiatives.
“Well, community engagement and awareness is of great influence. I think if awareness is carried out before that study, willingness will be there for participation. Community leaders are part of the community and people have trust in them. They cannot be overlooked.”20
“Community leaders play a big role in sensitizing their members for the clinical trial. So community awareness can enhance it.” 21
This important influence extended beyond the community, with participants expressing that government policies should ensure clinical trials are widely publicized and easily accessible.
“Government policies should make it easier and open so that participants would be comfortable for the trials.”22
DISCUSSION
By using a mixed methods approach, this study provides insights into patients’ perspectives on strategies for the enhancement of clinical trial participation in Nigeria. These analyses highlight a dynamic interplay between barriers and facilitators that impact recruitment and retention in cancer clinical trials. Key themes that emerged were: 1) minimizing study burden and side effects while optimizing incentives, 2) minimizing communication barriers and building trust through understanding, and 3) the importance of the context in which the trial is being run, including cultural and societal influence, as well as the healthcare infrastructure and government policies.
Both the quantitative and qualitative analyses emphasized the negative impact of clinical trials on transportation costs, medical costs, and frequent study visits. Transportation concerns(15),(16) and increased costs (16,17) associated with clinical trials have previously been acknowledged in both high-income countries (HICs) and low- and middle-income countries (LMICs) as barriers to trial participation. One way to reduce these barriers and facilitate enrollment is by offering incentives for transportation and improving flexibility in research visits. Strategies may include providing transportation assistance or offering telemedicine or home visits. If these practices are sustained, they could enhance long-term accessibility to trials for a broader range of patients.(16) Additionally, offering incentives such as stipends, meals, or health-related benefits may facilitate recruitment. However, incentives should be carefully designed to ethically encourage participation without coercion.
Communication was noted to be either a barrier when done poorly, or as a facilitator when done well. Clear, simple, complete and context-specific language is critical for both patient understanding and building trust in the research team. This is consistent with prior research showing that poor communication is an impediment to enrollment,(18) and participants are more likely to enroll if they receive full information.(19,20) Studies have also found that lengthy consents, written at a above 8th grade reading level can hinder comprehension.(21,22) Studies thus suggest a preference for discussions with research staff rather than reading the consent form.(23) Although fewer participants indicated that a lack of the recruiter’s fluency in their language would prevent participation, language barriers have been identified as a barrier to understanding the clinical trial process(24), and limited English proficiency is known to limit participation in clinical trials.(25–27) Recruitment of staff with good communication skills, language fluency, and cultural sensitivity specific to the needs of participants could help individuals to see the value of clinical trials and avoid alienization due to feeling unqualified or uncomfortable to engage in the process.
Health workers as research staff play a pivotal role as facilitators of trust and engagement. However, this study elucidates that it is not just the healthcare workers but also the overall environment that impacts participation in trials. While cultural differences between participants and researchers were less frequently noted as a barrier, they are known to significantly impact cancer clinical trials in LMICs.(28,29) Support from the immediate family was a critical theme that emerged from the qualitative review. This is less common in HICs, where participants often make individualized choices.(16) Thus, this may be very specific to each culture/community, and cultural influences should be considered in designing clinical trials. In this study, the state of readiness of healthcare facilities was also cited as a concern, and trust in the healthcare system was considered foundational. Research in HICs suggests that participants have considerable trust in medical institutions and researchers,(30) however, researcher’s credibility and expertise are important in building trust and facilitating participation.(31) If participants do not trust the people or organizations recruiting them, they may be hesitant to engage in the trial. Also, the physical environment, including equipment and drug availability, can directly influence an individual’s decision to engage in clinical trials. Respected individuals such as community leaders and elders can help to build trust between participants and the research team, (29,32) and involvement of these community members can also overcome language and cultural barriers.(29) Furthermore, the involvement of the government as an influential factor in support of clinical trials was noted to be an important factor that could influence the community at a larger level.
Strengths of this study include the diverse population spanning multiple regions in Nigeria and the mixed methods approach which allowed for a comprehensive understanding by integrating quantitative data and qualitative insights. The limitations of this study include recruitment through convenience sampling, potentially limiting generalizability of the findings. While 18 interviews provided rich qualitative data, this sample is limited and may not capture all perspectives. Only 6% of participants had previously participated in clinical trials, which may limit the applicability of findings to broader populations.
CONCLUSION
Barriers to cancer clinical trial participation in LMICs are multifaceted, including limited understanding of clinical trials, distrust of researchers/ the environment, and logistical challenges. Addressing these barriers requires culturally tailored strategies that enhance education, build trust, and mitigate structural inequities to improve recruitment and retention. By addressing patient-reported barriers and facilitators, clinical trial teams can implement multi-level strategies that build individual capacity, strengthen interpersonal relationships, streamline organizational processes, and leverage community engagement for sustained recruitment and retention.
Supplementary Material
CONTEXT.
Key objective
To identify factors from patients’ perspectives that hinder or facilitate recruitment and retention in cancer clinical trials in Nigeria.
Knowledge generated
The study highlighted multilevel barriers, including patient, provider, trial, and system-related barriers that hinder recruitment and retention in cancer clinical trials in Nigeria. The results also provided insights into factors that may positively impact participants’ willingness to enroll and remain in cancer clinical trials in Nigeria.
Relevance
Combined with data from our prior manuscript, evaluating providers’ perspectives, these data, specific to patients’ perspectives, may be useful in designing strategies to optimize participation and infrastructure for cancer clinical trials in Nigeria and similar low-resource settings.
Acknowledgment
We acknowledge members of the ICON-3 Practice-based Research Network (PBRN) for participating in the study and staff of the IVAN Research Institute who coordinated the study implementation.
Support
Supported by the National Cancer Institute of the National Institutes of Health under award number P50CA098252. The National Institutes of Health also supported E.E.E., B.O.O., N.I.-A., T.C.O., and I.U.I. time on this grant under award number 1UO1CA275118.
Footnotes
Declarations
The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
AFR reports that she is a current employee of Hologic, Inc. although the grant funding was obtained and the work primarily conducted while she was a faculty member at Johns Hopkins where she maintains an Adjunct Appointment.
Ethical Approval
Ethical approval for this research was obtained from the Nigerian National Health Research Committee (NHREC/01/01/2007–14/03/2023) and the John Hopkins Institutional Review Board. Informed consent was obtained from the participants before the commencement of both the quantitative and qualitative data collection.
Competing interests
The authors declare no potential competing interests
IDI; Male Respondent, South West
IDI; Female Respondent, Northeast
IDI; Male Respondent, Southeast
IDI: Female Respondent, Southwest
IDI; Female Respondent, Northwest
IDI; Male Respondent, Southeast
IDI; Male Respondent, Southeast
IDI; Male Respondent, Northeast
IDI; Male Respondent, Southeast
IDI; Female Respondent, Northeast
IDI; Female Respondent, Northeast
IDI; Female Respondents, Southsouth
IDI; Male Respondent, Southwest
IDI; Female Respondent, Northwest
IDI; Male Respondent, North Central
IDI; Male Respondent, Southwest
IDI; Female Respondent, Southeast
IDI; Female Respondent, Southsouth
IDI; Female Respondent, Southwest
IDI, Male Respondent; Southwest
IDI; Male Respondent, North Central
IDI; Male Respondent, Southwest
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