Improving African American women’s engagement in clinical research: A systematic review of barriers to participation in clinical trials

Abstract

Background:

Despite multiple efforts, African American women continue to be inadequately represented in clinical research while being overrepresented in disease, producing research results with limited generalizability to this specific population. Our understanding of the barriers to participation in clinical trials among racial/ethnic minority patients in general has evolved, but few studies have examined the reasoning behind African American women’s decision to not participate in clinical trials.

Objective:

The primary aim was to conduct a systematic review to identify the barriers reported by African American women regarding participation in clinical research to help explain the low levels of enrollment. We also suggest strategies that can be implemented by the research community to lessen the effect of those barriers.

Methods:

Searches were conducted through MEDLINE, SCOPUS, Web of Science, and Google Scholar. Following a set of eligibility criteria, a total of 18 peer-reviewed journal articles were selected and analyzed to render categories and themes.

Results:

Across studies aimed at examining their unique perspective, the reasons mentioned by African American women for not participating in clinical research were grouped in three broad categories: 1) weak relationship with the medical and research community, 2) high cost to participation, and 3) personal and “out-of-reach” circumstances. Reasons pertaining to participants’ relationship with physicians/researchers were most salient.

Discussion:

A targeted and comprehensive understanding of the barriers impacting African American women’s decision to participate in clinical research informs population-specific recruitment and research strategies for future studies. Additional studies assessing barriers to clinical trial research participation that intentionally report on disaggregated data by not only race/ethnicity but also sex are essential to improving the risk/benefit profile for a wide range of prevention and treatment efforts. This improved understanding of the differences between subgroups within minority populations has implications for bolstering culturally sensitive messages to enhance the engagement of minority communities in clinical trial research.

1.1. INTRODUCTION

More than 25 years have passed since the NIH Revitalization Act of 1993 was enacted to improve the representation of minorities and women in clinical research, yet the participation of minority women remains below that of men and Caucasian women.^1-3 Although African American women are overrepresented in both negative health conditions and disease,^4-7 they continue to be underrepresented in the efforts to find treatments for disease.

A better understanding of subgroups within minority populations is essential to improving the risk/benefit profile for a wide range of prevention and treatment efforts.^8,9 The importance of increasing African American women’s participation in clinical research extends to pediatric trials since mothers often play a pivotal role in the management of their children’s health and typically assume responsibility for health decisions, including their participation in clinical research.^10-12 Furthermore, studies report differences in factors that influence parental decision-making by race/ethnicity,¹³ suggesting that targeted recruitment efforts aimed at African American women have the potential to increase their participation in clinical trials, as well as the participation of their children.

Although the information on perceived barriers by African Americans in general exists,^14,15 there is little information about the reasons specifically mentioned by African American women to not participate in clinical research. This differentiation matters as previous research reports sex differences in reasons behind the willingness to participate in clinical trials.¹⁶ The current review focuses on African American women who are at particular risk of needing cutting-edge clinical care, yet are less likely to be a part of the studies that are essential to her receiving well-informed treatment. As far as we know, this systematic review is the first to assess African American women’s self-reported barriers to participation in clinical research irrespective of disease type. This information can be used by researchers to put in place culturally-responsive recruitment and research strategies that facilitate the participation of African American women, and their dependents, in clinical trial research.

1.2. METHODS

1.2.1. Search Strategy

The references identified for the systematic review were found using the following databases: MEDLINE, SCOPUS, Web of Science, and Google Scholar. Depending on the database, the following keywords were included as search terms or as part of the medical subject heading (MeSH) for the review: clinical trial*, clinical stud*, clinical research, health research, medical research, barrier*, challeng* difficult*, failure, trust*, refus*, enroll*, participa*, select*, perception*, perceiv*, recruit*; African American*, black*; women, woman and female. The syntax used for Google Scholar was shortened due to space limitations. Consistent with published recommendations (Bramer et al., 2017) the first 200 of the 18,900 articles resulting from the Google Scholar search were included in the review. Searches were filtered to include full-text journals published between 2000 and 2021.

1.2.2. Eligibility Criteria

Inclusion criteria were determined prior to the screening process. Studies were required to be conducted in the United States, available in English and focused on delineating barriers to the involvement of participants in clinical trials or clinical research. Only quantitative, qualitative, or mixed-methods studies in peer-reviewed publications with a clear description of methods, sample, data collection, and analyses were included in the review. Studies were limited to those that had adult African American/Black female subjects or that disaggregated their findings by race/ethnicity and/or gender.

1.2.3. Article Selection

The systematic review was performed through Covidence, an online systematic review platform. Results from the four databases were uploaded into this software and duplicates were eliminated. Two reviewers (OAP and HGO) independently screened the articles based on an initial scan of article titles and abstracts and conducted a full-text review of the remaining articles based on inclusion and exclusion criteria. If a discrepancy was noted during the screening or review process, the reviewers met to come to a consensus on whether to include the article in the extraction. The article identification process is delineated in Figure 1.

Figure 1:

Flow diagram of search methodology

1.2.4. Data Abstraction

From each study, the following information was gathered and extracted into a data table: author, year, article title, study design, study size and target population based on race and gender, study setting and method used, and the condition of interest as outlined in Table 1. Barriers described in articles were grouped into categories and then consolidated into themes. Table 3 reports findings by study and theme, in descending order for most endorsed barriers by AA women.

Table 1.

Characteristics of studies included in the systematic review

Author(s) Year	Title	Study Design	Study Size and Target Population	Study Setting	How Measured and Analyzed	Condition or Disease Studied
Baquet, C. et al., 2006	Recruitment and participation in clinical trials: Socio-demographic, rural/urban, and health care access predictors	Cross-Sectional mixed methods study	AA men and women white men and women aged 18+ Total Subjects, N=5154 AA women, N=561	Phone calls conducted in 13 of 24 Maryland jurisdictions	Survey conducted by telephone interview; descriptive analyses along with bivariate and multivariate analyses (software not specified)	Not Specified
BeLue, R et al., 2006	African Americans and participation in clinical trials: Differences in beliefs and attitudes by gender	Qualitative	AA men and women aged 19-65 Total subjects, N=67 AA women, N=35	Meharry Medical College Clinical Research Left (Nashville, Tennessee)	Focus groups by gender; employed grounded theory and content analysis to evaluate qualitative data using Atlas.ti 5.0 software	Not Specified
Brewer, L. et al., 2014	African American women's perceptions and attitudes regarding participation in medical research: The Mayo Clinic/The Links, Incorporated partnership	Cross-Sectional	AA women aged 20-87 Total subjects, N=381	The Links, Incorporated 38th National Assembly (Orlando, Florida)	Survey; descriptive analysis of survey data using SPSS v21.0	Not Specified
Brooks, M.M. et al., 2009	African American women and clinical trials: Perceived barriers to participation and potential solutions	Qualitative	AA women aged 18+ Total subjects, N=29	Women's Shelter, Professional women from federal agency, and church (Kansas), international religious fraternal order (Illinois)	Focus groups; interview responses coded and themes identified, along with demographic characteristics computed using Microsoft Excel XP database v5.1	Not Specified
Brown, D. et al., 2000	Recruitment and retention of minority women in cancer screening, prevention, and treatment trials: Predictors of intention to participate in chemoprevention trials for cervical neoplasia among minority and underserved women attending colposcopy clinics	Quantitative	AA, Latina, and white women aged 18+ Total Subjects, N=238 AA women, N=64	Colposcopy clinics at the University of Texas M.D. Anderson Cancer Left, Hermann Hospital, and Lyndon B. Johnson Hospital in Houston, TX	Questionnaires including hypothetical scenario of cancer trial; descriptive statistics and bivariate analyses (software not specified)	Cervical Cancer
	Recruitment and retention of minority women in cancer screening, prevention, and treatment trials: Influencing participation in a breast cancer clinical trial: patient and physician factors	Qualitative	AA and white women aged 18+ Total Subjects, N=196 AA women, N=61	Harper Hospital (Detroit, Michigan)	Interviews, physician assessment of eligibility, and documentation of actual trial participation; descriptive statistics of demographic information and bivariate analyses (software not specified)	Breast Cancer
Farmer, D. et al., 2007	Attitudes of African American and low socioeconomic status white women toward medical research	Cross-Sectional mixed methods study	AA and low SES white women aged 25+ Total subjects, N=72 AA women, N=52	Research Facilities (Winston-Salem, North Carolina)	Focus groups by age and race and questionnaire; interactive approach to qualitative data analysis, thematic codification for data reduction and thematic and variable-based analysis using QSR Nud*ist Software	Not Specified
Frierson, G. et al., 2019	Bridging the Gap: Racial concordance as a strategy to increase African American participation in breast cancer research	Qualitative	AA women aged 19-79 Total subjects, N=57	Academic medical school research facility, church or non-profit research institute (Rhode Island & Texas)	Focus groups and questionnaire; descriptive analysis using SPSS (2010) and thematic analysis using NVivo 8.0	Breast Cancer
Haynes-Maslow, L. et al., 2014	African American women's perceptions of cancer clincal trials	Qualitative	AA women aged 21-85 Total subjects, N=82	Community facilities (hospitals, churches, and community lefts) (North Carolina)	Focus groups and questionnaire; qualitative thematic analysis using Atlas.ti 6.0 and bivariate analysis of group differences	Cancer [Breast, Colon, Ovarian, Cervical, Lung, Skin, Hodgkin's, Non-Hodgkin's and Leg]
Lang, R. et al., 2013	African American participation in health-related research studies: indicators for effective recruitment	Mixed Methods study	AA men and women aged 18+ Total subjects, N=166 AA women, N=69	Triad region of North Carolina	Questionnaire; descriptive and inferential statistics, including multivariate statistical methods (logistic regression) using SPSS v19.0	Not Specified
Linden, H. et al., 2007	Attitudes toward participation in breast cancer randomized clinical trials in the African American community: a focus group study	Qualitative	AA women aged 30-65 Total subjects, N=58	Local African American church facilities or community facilities	Focus groups including questions about hypothetical clinical trial; descriptive analysis using SPSS v11, and qualitative thematic analysis using QSR Nudist 4.0	Breast Cancer
Martin, A et al., 2013	Recruitment of black and Latina women to a randomized controlled trial	Qualitative	AA and Latina Women aged 18+ Total Subjects, N=128 AA women, N=36	Not specified	Interviews; descriptive statistics and bivariate analyses using SAS, along with computation of weekly refusal rates and taxonomy of reasons for refusal	Post-partum depression
Newman, P. et al., 2006	HIV vaccine trial participation among ethnic minority communities: barriers, motivators, and implications for recruitment	Qualitative	AA men and women Latino men and women aged 18-68 Total subjects, N=58 AA women, N =8	Los Angeles	Focus groups; narrative thematic analysis and coding of text using Ethnograph qualitative software	HIV/AIDS
Owens, O. et al., 2013	African American men's and women's perceptions of clinical trials research: focusing on prostate cancer among a high-risk population in the South	Mixed Methods study	AA men and women aged 18+ Total subjects, N=81 AA women, N=43	Local Public Library (South Carolina)	Focus groups and survey; narrative thematic analysis using NVivo 9.0 and descriptive analysis using SPSS v18.0	Prostate Cancer
Rivers, D. et al., 2019	A community-academic partnership to explore informational needs of African American women as a primer for cancer clinical trial recruitment	Qualitative	AA women aged 24-80 Total subjects, N=42	West central Florida	Focus groups; qualitative data analysis using Atlas.ti and a combination of content analysis and constant comparison method	Cancer
Smith, Y. et al., 2007	Perceptions of clinical research participation among African American women	Qualitative	AA women aged 30-60 Total subjects, N=31	The University of Michigan Health System's National Left of Excellence (Michigan)	Focus groups; thematic content analysis (software not specified)	Not Specified
Trauth, J. et al., 2005	Factors affecting older African American women's decisions to join the PLCO Cancer Screening Trial	Qualitative	AA women aged 55-74 Total subjects, N=299	(Pittsburgh, Pennsylvania)	Interviews; descriptive statistics and multivariate analyses (logistic regression) (software not specified)	Cancer [Prostate, Lung, Colorectal and Ovarian]
Unson, C. et al., 2001	The effects of knowledge, attitudes and significant others on decisions to enroll in a clinical trial on Osteoporosis: implications for recruitment of older African-American women	Qualitative	AA women aged 67-86 Total subjects, N=16	Community Facilities (New England)	Focus groups; content and thematic analysis using group consensus and constant comparison method (software not specified)	Osteoporosis
Voytek, C. et al., 2011	Selectively willing and conditionally able: HIV vaccine trial participation among women at "high risk" of HIV infection	Qualitative	AA women aged 18+ Total subjects, N=17	Mobile recruitment or vaccine trial site's clinical office (Philadelphia, Pennsylvania)	Interviews; descriptive statistics and narrative thematic analyses using Atlas.ti	HIV/AIDS

NOTE: This table lists information on characteristics related to study design and methodology extracted from each article included in the systematic review.

Table 3.

Barriers to clinical trial

			Mistrust in the Medical And Scientific Community	Safely and Efficacy of Procedure or Medicati on	Fear of Experimentation or Randomization	Limited understanding/access to info about clinical trials	Time Commitment and/or location concerns	Patient- Researcher Relationship	Financial burden (i.e. inadequate insurance, no compensati on, lack of research funding)	Caregiving Duties	Inadequate Transport	Limited understanding of the informed consent process	Reputation of Medical Professional or Facility	Work Commitment	Unequa l Treatment	Religious Beliefs	Physical Discomfort	Lack of Interest	Unexpected Event (e.g., illness, incarnation, or oversleeping
Author/Year	Sample Size	Sex
Baquet, C. et al., 2006	561	Female								x	x
BeLue, R et al., 2006	35	Female			x			x							x
	32	Male	x		x				x			x	x
Brewer, L. et al., 2014	381	Female		x
Brooks, M.M. et al., 2009	29	Female	x		x	x		x	x				x		x	x
Brown, D. et al., 2000				x						x	x
Study 1	64	Female
Brown, D. et al., 2000						x		x		x
Study 2	61	Female
Farmer, D. et al., 2007	61	Female	x	x	x		x			x		x		x	x		x
Frierson, G. et al., 2019	57	Female	x		x	x	x	x	x		x
Haynes-Maslow, L. et al., 2014	82	Female	x			x		x	x		x					x
Lang, R. et al., 2013	69	Female	x				x						x					x
	35	Male	x				x
Linden, H. et al., 2007	58	Female	x	x	x	x	x		x	x	x			x		x
Martin, A et al., 2013	36	Female					x						x					x
Newman, P. et al., 2006	8	Female		x
Owens, O. et al., 2013	43	Female	x	x	x	x	x			x		x		x
	38	Male	x	x	x	x	x			x		x		x
Rivers, D. et al., 2019	42	Female	x	x	x	x			x				x
Smith, Y. et al., 2007	31	Female	x			x	x	x	x	x				x
Trauth, J. et al., 2005	299	Female	x	x	x	x		x				x
Unson, C. et al., 2001	16	Female	x	x	x			x			x				x
Voytek, C. et al., 2011	17	Female	x	x	x		x		x	x		x					x		x

NOTE: This table lists each study included in the systematic review and whether the specific barrier to participation in clinical trials was identified by the study’s male and/or female subjects.

1.3. THEORY

Several theories have been proposed to study and predict health-related behavior;¹⁷ however, a criticism of these theories is that they do not take into consideration the social and environmental determinants of health.¹⁸ For example, the Theory of Planned Behavior (TPB) which proposes that an individual’s intentions are influenced by their attitudes and social norms,¹⁹ is relevant to participation in clinical trials in that the stronger the intention is, the more likely the person will engage in the behavior. Yet, contextual or organizational factors that may influence an individual’s intention to participate in clinical research are not accounted for in this theory. Several other emerging theories take environmental conditions under consideration, however, it is a challenge to test these without more information illuminating the reasons that African American women do not participate in clinical research. One theory is the salutogenic model which considers the factors responsible for creating and maintaining good health.^20,21 Centrally, the model looks at the relationship between life stressors and an individual’s health status and how a sense of coherence explains this connection. The theory posits that if there is a strong sense of coherence, the individual is better able to deal with stressors which fosters better health. Alternatively, the life course analysis theory proposes that health decisions interact with economic, social, and psychological factors throughout the whole life course.²² For example, there is a finding that socio-economic status is impacted by early life circumstances (e.g., low birth weight).²³ We aspire to help change the behavior of African American women to engage in clinical trials; however, it is important to consider the precursors of an individual’s beliefs that influence their attitudes, perceived behavioral control, and norms that then contribute to their intention which leads to behavior. Our review will inform our understanding of the factors that contribute to a health decision and assist in adopting a theory to guide our hypotheses about how to effect change in health decisions.

1.4. RESULTS AND DISCUSSION

From a total of 1424 studies identified, 18 peer-reviewed journal articles met the eligibility criteria and served as the basis for this review. The two most common reasons for exclusion of the study upon full-text review included not being about barriers to clinical trial participation and that results were not disaggregated by race/ethnicity and/or gender. Several studies were excluded because the subjects were not our target population but professionals who shared their perspectives about potential barriers to African American women’s enrollment in clinical trials.

The studies included in the review were published between 2000-2019 and sample sizes of AA female participants ranged widely from 8 to 561. The majority of studies (n=16, 89%) had fewer than 100 participants and most of the study designs were qualitative in nature, using focus groups and interviews as preferred methods. Fifteen of the 18 studies (83%) included only women as research participants, while the remaining three included both AA men and women. With regard to the diseases studied, seven (39%) of the articles did not specify the disease or condition associated with the study, while the majority of the remaining articles assessed participation in clinical trials for varied cancer types (n=7, 39%), two involved perceptions of participation in HIV vaccine trials (n=2, 11%), one on participation of AA women in clinical trials on postpartum depression (n=1, 6%), and one on a clinical trial of osteoporosis (n=1, 6%). Two studies (Trauth, J. et al., 2005 & Unson, C. et al., 2001) focused on participation in cancer and osteoporosis trials and were more specific in their reporting of participants’ ages, while the remaining studies listed a broad age range (i.e., 18+ or 24-80) in the description of their subjects making it difficult to consider the role development or life course factors may play in the types of barriers reported by AA women.

A total of 17 distinct reasons for not participating in clinical research were expressed by participants of the 18 studies (see Table 2). The barriers represent some personal characteristics as well as a variety of social, economic, and environmental conditions, which are often called the social determinants of health, that can strongly influence individual decision-making and experiences. These 17 identified barriers to clinical trial participation are analyzed and discussed here grouped in three categories: (1) weak relationship with the medical and research community, (2) high cost to participation, and (3) personal and “out-of-reach” concerns.

Table 2.

Barriers to clinical trial participation identified by gender

Barrier	Both Men and Women (disaggregated by gender)	Men Only (disaggregated by gender)	Women Only (disaggregated by gender)	Only Women included as research participants	Article n(%)
Mistrust in the Medical and Scientific Community	2 (11%)	1 (6%)	0 (0%)	10 (56%)	13 (72%)
Safety and Efficacy of Procedure or Medication	1 (6%)	0 (0%)	0 (0%)	9 (50%)	10 (56%)
Fear of Experimentation or Randomization	2 (11%)	0 (0%)	0 (0%)	8 (44%)	10 (56%)
Limited understanding/access to information about clinical trials	1 (6%)	0 (0%)	0 (0%)	8 (44%)	9 (50%)
Time commitment and/or location concerns	2 (11%)	0 (0%)	0 (0%)	6 (33%)	8 (44%)
Patient-Researcher Relationship	0 (0%)	0 (0%)	1 (6%)	7 (39%)	8 (44%)
Financial Burden (i.e. inadequate insurance, no compensation, lack of research funding)	0 (0%)	1 (6%)	0 (0%)	7 (39%)	8 (44%)
Caregiving Duties	1 (6%)	0 (0%)	0 (0%)	6 (33%)	7 (39%)
Inadequate Transportation	0 (0%)	0 (0%)	0 (0%)	6 (33%)	6 (33%)
Limited understanding of the informed consent process	1 (6%)	1 (6%)	0 (0%)	4 (22%)	6 (33%)
Reputation of Medical Professional or Facility	0 (0%)	1 (6%)	1 (6%)	3 (17%)	5 (28%)
Work Commitment	1 (6%)	0 (0%)	0 (0%)	3 (17%)	4 (22%)
Unequal Treatment	0 (0%)	0 (0%)	1 (6%)	3 (17%)	4 (22%)
Religious Beliefs	0 (0%)	0 (0%)	0 (0%)	3 (17%)	3 (17%)
Physical Discomfort	0 (0%)	0 (0%)	0 (0%)	2 (11%)	2 (11%)
Lack of Interest	0 (0%)	0 (0%)	1 (6%)	1 (6%)	2 (11%)
Unexpected even (s)- i.e. illness, incarnation, or oversleeping	0 (0%)	0 (0%)	0 (0%)	1 (6%)	1 (6%)

NOTE: This table details barriers to participation in clinical trials identified across studies and the number of studies including male and/or female subjects.

(1). weak relationship between African American women and the medical and research community.

Reasons that have to do with a hindered relationship with their physicians and with the research enterprise as a whole were the most frequently mentioned barriers to participation in clinical research. In 50% or more of the studies, participants cited: (1) mistrust in the medical and scientific community (n=13, 72%), (2) concern for safety and efficacy of procedures or medications (n=10, 56%), (3) fear of experimentation or randomization (n=10, 56%), and (4) a limited understanding of and access to information about clinical trials (n=9, 50%). Other barriers that were mentioned included: concerns with the patient-researcher relationship (n=8, 44%), a limited understanding of the informed consent process (n=6, 33%), the reputation of the medical professional or facility (n=5, 28%), and unequal treatment (n=4, 22%).

The strong mistrust that the African American community, and specifically African American women, feel towards research in general is evident from this review, and many discussed the lasting effect that the historical deception and mistreatment endured by African Americans in the Tuskegee syphilis study has had on their current decisions about participating in clinical research. Some studies (n = 2) concluded differently and reported that willingness to participate in clinical trials does not significantly differ between Whites and minorities, particularly among those with previous exposure to clinical research.²⁴ This systematic review found, however, that when African American women are asked specifically about their willingness to participate in clinical trials, issues of mistrust are salient. Concerns related to trust and relationships can be reduced by using a community-engaged approach and purposefully involving patients and lay members of the public in the design of recruitment and retention strategies and patient-facing information²⁵ and developing explicit structures of accountability within research teams²⁶ (e.g., with the establishment and ongoing use of a community advisory board). Studies that encourage patients and providers to create a sense of common purpose, support, and understanding may assist in reducing bias and increasing trust and cooperation.²⁷ This can, for example, involve building teams that are representative of diverse participants but also individuals that represent individuals’ communities.²⁶

Alluding to the lack of trust toward the research enterprise, fear of experimentation or randomization included participants' aversion to any association with exploited research animals. Minority patients may have additional concerns about the ethical motivations of clinical trial research. Fear-based barriers can be minimized by the introduction of patient navigation. While patient navigators can be lay community members or formally trained as nurses or social workers, many patient navigation programs tend to employ individuals who are racially, ethnically, and culturally matched to the population they serve and who are more often than not, bilingual.^28,29 Striving to encourage African American women who do participate in clinical trials to share their experience with others and to encourage them to become more actively involved in future research, particularly as patient navigators or lay health workers, can potentially help combat some of the fear-related concerns that may discourage African American women’s participation in clinical trials. Further research is needed, however, to provide a more complete portrayal of how fear, as well as mistrust, can be either intensified or mollified by other factors at play. Neglecting to directly address these issues can fuel the damaging cycle of fear and mistrust that appears to undergird low levels of enrollment in clinical trials and produces inadequate care for African American women and their children, which in turn produces greater fear and mistrust.

Concerns with the safety and efficacy of experimental procedures and medications included mention of both short-term, immediate health consequences (e.g., becoming sick) as well as long-term damage to one’s wellbeing (e.g., disability, death). This important self-identified barrier to clinical trial enrollment among African American women relates to the patients’ and providers’ difficulty in coping with the uncertainty that is inherent to clinical trial participation. Specifically, patients and providers may struggle to assess the risk-benefit ratio and may overweigh the probability and severity of various types of adverse outcomes associated with clinical trial participation. Uncertainty about risk may complicate the informed consent process or impede providers from offering clinical trials to their patients altogether. Predicting and managing this uncertainty represent key components of the decision-making process.

One way to help overcome concerns around the safety and efficacy of procedures and medications that may discourage African American women from participating in clinical trials involves provider consideration of patient concerns, needs, and preferences to enable shared decision-making.^30-32 The reluctance of both patients and providers, respectively, to participate in and offer clinical trials may be partially addressed by strategies to improve communication and mutual understanding.³⁰ For example, Hamel, et al.²⁷ recommend using question-prompt lists (often a list of questions related to the physical and psychosocial aspects of a medical condition that patients can ask their clinical teams during clinic visits) to encourage informed clinical trial participation by minority populations.²⁷ Having an opportunity to hear and address patient concerns (e.g., by letting patients know of treatment options for potential adverse effects) could additionally help providers feel more secure in maintaining their patients’ trust.

Relatedly, participants report the lack of information about the objectives of a study and procedures, as well as the informed consent process, hindering their capacity to make an informed decision about participating. Educational efforts for African American women should focus on improving their understanding of clinical trials beyond their knowledge of the term being related to research.³³ Barriers related to clinical trial knowledge can be ameliorated or overcome through a combination of strategies such as enhancing information provision and reducing study complexity for interested patients, as well as allowing marketing and enrollment materials to be designed in a way that is culturally-appropriate, engaging, and ensures patients are supported throughout the entire enrollment and study processes. Information about clinical trials and study materials should be designed in a way that is straightforward and easy to understand, while the details of what a participant is consenting to should be transparent and easy to identify.

Studies to improve provider attitudes and communication skills (including focusing on communication skills and trial-related attitudes) related to discussing trials with minority patients can further help minimize barriers specifically pertaining to clinical trial knowledge. Research has shown that minority patients are more likely to have lower-quality communication with their physicians, which can reduce the opportunity to adequately address questions and further exacerbate mutual concerns between patients and providers.³⁴ Adequately improving the communication between patients and providers to facilitate discussion of patients’ limited understanding of and/or concerns about clinical trials may, therefore, empower providers to have greater confidence that patients fully understand study participation requirements and have the measures in place to enable full adherence to study requirements.

(2). High cost to participation.

Concerns with both the physical (time commitment and/or location) and financial burdens that their participation in a study would imply (inadequate insurance, no compensation, lack of research funding) were mentioned in 8 studies (44%). Along the same lines, between 22% (n=4) and 39% (n=7) of studies mentioned caregiving duties, inadequate transportation, and competing work commitments. These reasons refer to the cost/benefit analysis participants perform when making decisions to participate in clinical research. It appears the benefits often do not outweigh the costs of participating in a study (e.g., losing wages, losing time traveling to appointments, needing to arrange for a babysitter, having to arrange for coverage at one’s job). Patients must be provided clear and transparent information about the potential of any trial-related burdens, including information about options to help with said burdens such as financial support and other assistance. Renewed efforts to improve representative patient participation in clinical trials may be partially addressed with incentives to accomplish these goals; this can include ethically appropriate financial assistance for trial-related out-of-pocket expenses and/or direct accommodations for travel, meals, childcare, and/or lodging for participants (and their families) in clinical trials.^30,35

(3). Personal and “out-of-reach” reasons.

Between 6% (n=1) and 17% (n=3) of studies mentioned religious beliefs, physical discomfort, lack of interest, and unexpected events (illness, incarceration, oversleeping) as reasons for having not participated in clinical research. With the lowest frequency, these issues are considered less susceptible to researcher influence.

This systematic review, therefore, suggests that African American women would participate in clinical trials if the conditions for their participation were optimal (e.g., if they had trusting and healthy relationships with their healthcare providers, if they had clear and accessible information about clinical trials and their risks, if there were tangible ways to reduce the social and financial burdens of participation).

Improving Representation of African American Women in Clinical Trial Enrollment: A Recruitment Mindset.

Effective participant recruitment is vital to the success of clinical trials;^30,33 it should be just as important as any other component in research study design. Overcoming the aforementioned barriers and bolstering enrollment rates necessitate the development of a “recruitment mindset”; it requires the research team to intentionally establish community partnerships and carefully conceptualize engagement strategies³⁶ by which participants are invited to participate in research programs in a respectful way.³⁷ Having a “recruitment mindset” involves engaging stakeholders (e.g. African American women) when developing research protocols and processes so that they are created intentionally with the participants’ needs firmly in mind.^38,39 A comprehensive and effective approach should include commitment and investment via a well-planned budget that allows the time, resources, and expertise to enhance stakeholder relationships, increase communication, and support the translation of community preferences and values into recruitment plans and activities.

Another aspect of a recruitment mindset is being innovative in how to communicate messages about participating in clinical research. As with any efforts, regardless of topic, education and public awareness approaches can miss the people who may most benefit from the information. One innovation is to use social marketing strategies to help reframe and combat the barriers to clinical trial participation by African American women. First, a social marketing approach would be engaging in deep formative work to understand the psychological mindset of African American women and develop messaging strategies that directly address their mindset. In that sense, a review like this one can serve a social marketing team. Working with a community of stakeholders would be critical to creating an effective social marketing campaign.^40-42

Second, regarding the development of message strategies, it is critical to develop messages that address and reduce fears. Thus, the use of hope, pride, or warmth may be options worth exploring.^43-46 Likewise, using a narrative/storytelling strategy is an effective way to engage the audience, increase empathy, and compel them to change their mind about a behavior.^47,48 Third, the source (i.e., spokesperson) delivering the targeted message should be a trustworthy and credible African American female.^49-52 The specifics would be determined in the formative research stage and could be someone identified from the clinical setting or the local community. Finally, the channel used is critical. Once effective messages are created and pilot-tested, they must be distributed via channels that will reach the target audience. If this is an audience that often visits hospital settings, for example, the messages will need to be visible in that setting. Social media is compelling because 85% of American adults own a smartphone; in particular, minorities and lower-income Americans depend on their smartphones for online access.⁵³ A text-messaging campaign should also be pursued.^54-56 Notably, the most effective campaigns use multiple channels to reach audiences: social media, text, posters in clinics, videos playing in waiting rooms, amongst others. The use of all channels could be coordinated simultaneously to maximize impact.^57,58

Limitations.

This study has several limitations that need to be considered. First, this review includes only peer-reviewed literature, and not “gray” literature which could have provided additional information. The low number of available studies (18) for this review also limits the reach of its conclusions, given that studies varied in terms of whether the participating women had a current diagnosis or were at high risk of developing a medical condition, or whether participation in research was more of a hypothetical question. Some studies (5)^59-63 asked women more generally about participating in research, while others (7)^{64,65,33,66-69} asked women about participating in studies that would specifically address a current or potential health ailment. Women might respond differently depending on those circumstances, and there is insufficient information here to identify those differences. This review also did not include any studies where women responded on behalf of their children, expressing whether or not they would allow or encourage their children’s participation in research or whether there are unique considerations for study enrollment specific to African American mothers. Women’s responses might be different if they consider the possible health benefits or risks to their children and their participation as patients or healthy controls in clinical trials.

The results of this review show the importance of the barriers mentioned in this discussion and highlight the need for further studies that address how African American women’s views of participation in clinical research may be influenced by their role as mothers, their diagnoses, and disease severity. The salience of the barriers is a strong argument for revisiting the research community’s approach to study recruitment with African American women and underscores the need to strengthen not only the provider-patient relationship but also the relationship of providers and researchers with the African American community as a whole. Lastly, the social marketing approaches suggested in this paper offer new ways to open dialogue opportunities with African American women on the subject of participation in clinical studies.

1.5. IMPLICATIONS

Although some studies have demonstrated that access to research opportunities is critically impacted by systemic barriers (e.g., poor hospital infrastructure, eligibility criteria limiting participation or inclusion, failure to reach diverse groups due to recruitment limitations, perceived burden on staff given challenging recruitment and retention tactics),^38,70-72 studies included in this review particularly emphasized the importance of individual (e.g., patient, provider) and relationship factors (e.g., between the participant and researcher). Given that the focus of this systematic review was solely on the reasons provided by African American women to not participate in clinical research, it therefore sheds light onto the elements that play a role in African American women’s decision-making when faced with the opportunity to join a clinical trial. The findings here can be used to inform broader multilevel models that explain enrollment in clinical trials,²⁷ as well as the design and implementation of comprehensive enrollment strategies, by contributing information that comes directly from the patients’ voice.