- Email: [email protected]
Exploring Donotion-related Knowledge Attitudes, Beliefs and Distrust Among African Americans
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Exploring Donation-related Knowledge, Attitudes, Beliefs and Distrust Among African Americans Dana HZ Robinson, M.P.H., Jennie P. Perryman, Ph.D., R.N., Nancy J. Thompson, Ph.D., M.P.H., C. Lamonte Powell, Ph.D., M.P.H., Kimberly R. Jacob Arriola, Ph.D., M.P.H.
Financial disclosures: We do not have any financial involvement with or financial interest with any organization or entity with a financial interest in this subject matter or materials disclosed in this manuscript. This research was supported by the National Institute of Diabetes and Digestive and Kidney Diseases (Grant 5 R01 DK79713-05). Abstract: Within the field of organ donation, multiple studies have shown differences in patterns of trust, however, it is unclear which elements are significantly related to donation decision making among African Americans. This study sought to disentangle the construct of trust by parceling out measures related to the healthcare system, the donation/allocation system, and the physician; and determine the relationship of these dimensions to attitudes toward organ and tissue donation. Cross-sectional survey data were gathered from 585 African American adults residing in the Atlanta metropolitan area. Results indicate that varying dimensions of trust function differently in their influence on attitudes toward donation. Our findings suggest that trust is critical to donation decision-making and should be measured with a multidimensional approach, particularly among racial/ ethnic groups with complex histories with the healthcare system. This study underlines the need for a more tailored, individualized approach to promoting organ and tissue donation among African Americans. Acknowledgements: We also thank Rianot Amzat, Mohua Basu and Rhonda DeLaremore for their assistance with data collection, cleaning, entry, and analysis.
Author Affiliations: Dana HZ Robinson, M.P.H., Rollins School of Public Health, Emory University; Jennie P Perryman, Ph.D., R.N., Emory Transplant Center, Emory Healthcare; Nancy J Thompson, Ph.D., M.P.H., Rollins School of Public Health, Emory University; C. Lamonte Powell, Ph.D., M.P.H., Rollins School of Public Health, Emory University; Kimberly R Jacob Arriola, Ph.D., M.P.H., Rollins School of Public Health of Emory University Correspondence: Dana H. Z. Robinson, Department of Behavioral Sciences and Health Education, Rollins School of Public Health of Emory University, 1518 Clifton Rd, Rm 521, Atlanta, GA 30322, Tel: (404) 727-2386, Fax: (404) 727-1369, [email protected]
INTRODUCTION
A
frican Americans (AAs) are disproportionately represented on the national transplant waiting list. While representing 13% of the U.S. population,1 AAs account for approximately 30% of the 123,000 transplant waitlist candidates.2 The need among AAs, in particular, is considerably high due to the disproportionate impact of certain health conditions (e.g., diabetes, hypertension, heart disease, hepatitis) that potentially warrant need for life-saving transplants. Nationally, the incidence rate of ESRD among AAs is 3.4 times greater than that among Whites.3 In the state of Georgia, where the present study was conducted, AAs comprise the majority of candidates on the kidney waiting list (63%) whereas nationally they represent a much smaller proportion of candidates (34.1%).2 African Americans are also overrepresented on the transplant waiting list, due in part, to the lack of 42 VOL. 107, NO 3, SUMMER 2015
histocompatible donors. The kidney matching process is heavily dependent on the similarity of ABO blood groups and protein complex HLA-human leukocyte antigens.4 Greater heterogeneity exists among AAs in their histocompatibility antigens compared to Whites; thus antigen-matched organs for AA patients are in greater demand.5 This difficulty is exacerbated by the underrepresentation of AAs in the donor pool and speaks to the necessity of increasing the number of potential AA donors.6 Negative attitudes towards donation play a prominent role in the lack of willingness among AAs to donate. Additional reasons for continuing lower donation rates include: (1) Lack of knowledge and awareness of the topic of donation and transplantation; (2) Religious myths, misperceptions and superstitions; (3) Fear of premature death; (4) Concerns about racism/classism and transplant system inequities; and (5) lack of trust in healthcare systems.7,8 Taken together, these factors contribute to AAs spending more than twice the amount of time on the national transplant waiting list compared to Whites.9 African American History of Distrust of the Healthcare System. Research suggests that a lack of trust in the health care system is an important factor in decisionmaking regarding organ donation.10–14 This overarching sense of distrust also expands to influencing care-seeking behavior,15–17 undermines participation in research,18,19 and even influences the signing of living wills.20 Patterns of negative interactions with the healthcare system21 coupled with centuries of exploitation by the medical establishment have laid a foundation for a pervasive sense of distrust.15 Trust and Attitudes related to Organ Donation. Concerns about race and class-based inequalities are severe limiting factors with respect to organ donation.23 While this reluctance, in part, may be due to a lack of understanding of how the process of organ donation and transplantation works,24 genuine fears of discrimination and exploitation have perpetuated overall feelings of distrust of the medical establishment. Concerns have been raised about the fairness of the organ allocation system such that many feel that they will not receive the same quality of care as Whites25 and others feel that consenting JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
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to donation might hasten death.26 These misgivings associated with the field of medicine and equity within the healthcare systems influence attitudes about organ donation and subsequently affect the rates at which people are willing to become organ donors.27 Barriers to donation for the AA population are welldocumented but not necessarily well understood. Thus, research in this area is necessary for the development of culturally-sensitive interventions that shape AAs’ attitudes and donation intentions. Measuring Trust. In the literature, trust is widely acknowledged as an essential component in health-related interactions. Research has found that trust is fundamental in patient satisfaction, adherence to prescribed medical advice, as well as positive health outcomes.28,29 Multiple dimensions of trust have also been identified in relation to the different components of the healthcare system.30–32 Divergent experiences may result in varying levels of trust and, therefore, warrant a multidimensional approach. The trust that one has in his/her physician may differ from trust in hospitals, as well as in private or government entities. It is suggested that these varying interactions can be categorized into two distinct aspects of trust: (1) interpersonal/physician and (2) system/social trust. Interpersonal trust is developed over time and based on individual experiences with a provider.30–32 Conversely, system/social trust is often referenced by past experiences, general impressions, societal views, and second-hand interactions with professional health and medical institutions.30–32 Despite extensive research into the role of trust, there has been very little effort to systematically explore trust as a pathway and/or its interrelationships with attitudes in shaping donation-related behavior. While, explanatory models that explore trust and other constructs that shape attitudes toward organ donation are scarce, one notable exception is a conceptual model of trust in the medical profession, proposed by Hall et al.33 In this model, the authors posit that general trust (characterized by attitudes toward a broader, social, professional medical system) and physician trust are related measures but differ significantly in their influence on certain patient attitudes and behaviors.33 Previously this model was used in a clinical setting in the context of patient satisfaction with care and willingness to adhere to recommendations; however, it is our purpose to expand this model for use in the context of organ donation. Within the field of donation, multiple studies have shown differences in patterns of trust.17,30,32,34,35 However, it is unclear which elements are significantly related to donation decision making among AAs. The construct of trust has numerous components and most studies that address organ donation behavior use a single trust JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
scale that is composed of a conglomerate of items.12,14,36 Oftentimes these items muddle the different dimensions of trust. The proposed study makes novel contributions to the field of donation by disentangling and creating a deeper understanding of this concept of trust. From a theoretical perspective, the relationship between attitudes and behavior has been widely studied.37 Specifically, organ donation beliefs and attitudes have been reported as significant predictors of both willingness to donate and the expression of donation intentions.38 Trust is equally important and has also been studied extensively with regards to its influence on donation behavior.24,39 Both of these core components are integral to the donation decision making process, however, the degree to which they influence one another has yet to be explored. The purpose of this study was to modify the Hall et al.33 conceptual model of trust and increase its cultural relevance to AAs by exploring the relationship between trust and attitudes toward donation. This adapted model incorporates a broader measurement of trust and differentiates among three types of trust. We distinguished between physician trust and two types of system-level trust (healthcare system and donation/allocation system) and investigated how these constructs are related to attitudes toward organ donation. This study was guided by the following hypotheses: 1. Trust in the healthcare system is associated with positive attitudes toward donation. 2. Trust in the donation/allocation system is associated with positive attitudes toward donation. 3. Physician trust is associated with positive attitudes toward donation.
METHODS Study Design. The present study is part of a larger study testing the effectiveness of a culturally-sensitive organ donation intervention for AA adults. The parent study uses a randomized, pre-post design with a control group; data from the current study were collected during the baseline assessment (March to December 2009). Using a crosssectional research design, the current study combined baseline data from both intervention and control groups. Community Health Advocates & Participant Recruitment. Community Health Advocates (CHAs40) facilitated participant recruitment. There were a total of 19 CHAs selected based on their demographic similarity to our target population and their ability to bring together a variety of people. Each CHA was trained and tasked with recruiting a total of 32 participants into the study from members of their social networks (church, professional or community affiliations, family, friends, and associates). Each CHA hosted multiple group educational sessions in which participants watched a video, engaged VOL. 107, NO 3, SUMMER 2015 43
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in group discussion and completed a questionnaire. Group sessions were conducted in a comfortable environment at either the CHA’s home or at a private location in the community (e.g., community center, library, church, fire station community room). Participants were recruited with the understanding that they were participating in a two-hour, group, health-related discussion and would be compensated $15 in appreciation for their time. Participants were considered eligible if they selfidentified as Black or AA (for the purpose of this study, the term “Black” includes people of African descent, regardless of cultural identification) and were 18 years of age or older. Prospective participants read and signed the consent form and completed the baseline questionnaire independently. This study was conducted with University Institutional Review Board approval. Measures. Participants completed a survey that included measures of attitudes/beliefs regarding donation and transplantation; healthcare, donation/allocation systems, and physician-level trust; and demographic characteristics. A total of four scales were used. Below are descriptions of each individual scale: Attitudes and beliefs toward organ donation/ transplantation were captured using a 13-item scale.41–43 This scale included items that measured support for and concerns about donation such as “organ donation is a cause worth supporting” and “I believe it’s important for a person to have all of their parts when buried”. Response options for these items ranged from 1 (strongly disagree) to 5 (strongly agree); higher scores indicated more positive attitudes towards organ donation, and total scores ranged from 25 to 65 (M=53.3, SD=7.2; α =.86). Trust in the healthcare system was measured using a 5-item scale.44 This scale examined participants’ attitudes regarding the existence of discrimination and racism within the healthcare setting using items such as, “patients have sometimes been deceived or misled at hospitals” and “hospitals have sometimes done harmful experiments on patients without their knowledge.” Participants were asked to indicate their agreement with the statements using a 5-point scale ranging from 1 (strongly disagree) to 5 (strongly agree), higher scores indicated more trust of the healthcare system, and scores ranged from 5 to 25 (M=14.1, SD=3.3; α=.72). Trust in the organ donation/allocation system was measured using a 4-item scale, adapted from previously developed scales43,45 that specifically addressed aspects of discrimination and economic equity in the organ donation/allocation system. Sample items included, “racial discrimination prevents minority patients from receiving organ transplants they need” and “organs can be bought and sold on the black market in the United States.” In this 44 VOL. 107, NO 3, SUMMER 2015
study, participants indicated their level of agreement from “strongly disagree” to “strongly agree,” and scores ranged from 5 to 20 (M=12.8, SD=2.8; α =.61), with higher scores indicating more trust in the donation/allocation system. Physician trust was measured using a 3-item scale.42 This scale examines the level of trust that participants specifically have in physicians. It addresses issues of trust with regards to organ donation such as, “I think that doctors would try just as hard to save my life whether or not I plan to be an organ donor.” In this study, response choices ranged from strongly disagree to strongly agree on a 5-point, Likert scale with scores ranging from 3 to 15 (M=11.6, SD=2.1; α =.70), such that higher scores indicated more trust in one’s physician. Demographic Characteristics included measures of age, gender, educational attainment, employment, income, marital status and personal experiences with donation. The personal experiences with donation scale captured whether people were personally impacted by the donation system. On this scale, respondents were asked to respond ‘‘yes’’ or ‘‘no’’ to nine author-created items such as ‘‘I know someone who donated an organ while living,’’ and ‘‘I know someone who received an organ transplant.’’ Respondents’ scores represent the number of items to which they responded favorably. Since the scale did not seek to measure a one-dimensional construct, no effort was made to demonstrate internal consistency of the items. Statistical Analyses. Participant demographic characteristics were first analyzed using descriptive statistics, then analyzed in relation to each study variable in the model. Pearson correlations were used to explore the relationship between age and the continuous variables to be included in the model (i.e., trust in the healthcare system, trust in the organ allocation system, physician trust, and attitudes toward donation). One-way Analyses of Variance (ANOVA) were used to determine the associations between the categorical variables education, income, and personal experiences with donation and continuous variables cited above. T-tests were used to explore associations between dichotomous variables of gender, marital status, and employment and continuous variables cited above. Based on significant bivariate findings, those variables that were related to one of the trust variables (predictor variables) and/or the outcome variable of beliefs/attitudes were entered into the regression model. Next, an ANOVA was conducted to address the possibility of nesting and determine whether participants recruited by a given CHA held more donation beliefs that were more similar to each other compared to participants who were recruited by another CHA. First, we created a dummy variable for “CHA” to use as the independent variable. Next, we conducted an ANOVA to test whether JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
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between-CHA variability in donation beliefs (across CHAs) was greater than within-CHA variability in donation beliefs (within a CHA group). Results from this analysis were not significant (p=.29); therefore, we did not control for CHA in the regression model. A series of multiple linear regressions were conducted to assess the relationship between each of the trust variables and attitudes toward donation. We present a full model that includes all three trust variables and then three stepdown models that explore the independent relationship of each of the variables to dependent variable. All models control for educational attainment, gender, employment and personal experiences with donation. An α of .05 was used to determine statistical significance. Post-hoc Analyses. A mediation analysis was conducted using the macros PROCESS Procedure for SPSS46 in order to better understand the relationship between trust in the donation/allocation system, physician trust, and attitudes toward donation. The PROCESS macro was chosen for its ability to compute the indirect effect by calculating the product of coefficients. The custom dialog file was installed in SPSS and linear regression was conducted between trust in the donation/allocation system, physician trust, and attitudes toward donation. All models controlled for educational attainment, gender, employment and personal experiences with donation. An α of .05 was used to determine statistical significance.
RESULTS Description of Study Participants. At baseline, a total of 585 participants completed the survey, the majority of whom were female (69%; see Table 1). Similar proportions of the sample reported that their highest level of educational attainment was high school (39%) or college (42%). Similar proportions of participants also reported being single/never married (37%) and married (39%). Participants tended to report working full or part time (63%), the majority had health insurance (78%) and ages ranged from 19 to 96 years (M=46.3, SD=14.6). About one-third of participants were recognized as donors on their driver’s licenses. Participants held positive attitudes toward donation (M=53.2, SD=7.2), and had minimal personal experiences with the organ donation/transplantation system (M=2.9, SD=2.1). Bivariate and Regression Analyses. The next analyses explored the demographic variables in relationship to each of the study variables to determine whether they would be included in the regression model (see Table 2). Age was not related to attitudes toward donation (r = .03, p>.05) or any of the trust variables [healthcare system (r = .05, p>.05), donation/allocation system (r =.03, p>.05), physician trust (r = .02, p>.05)]. Gender was significantly related to all of the study variables, such that JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
Table 1. Demographic Characteristics of Study Participants (N=585)
Characteristic
N (%)
Mean age in years (range)
46.2 (19–96)
Female
398 (69.2)
Race/Ethnicity Black/African American
499 (87.1)
Black/Caribbean
52 (9.1)
Black/Hispanic
9 (1.6)
Other
13 (2.2)
Educational Attainment Less than high school
29 (5.1)
High school graduate or GED
224 (39.4)
Completed college
237 (41.7)
Professional degree
79 (13.9)
Employment status Unemployed
118 (20.9)
Retired
91 (16.0)
Working part or full time
361 (63.3)
Marital status never married
208 (36.9)
married
225 (39.2)
divorced/separated/widowed
115 (23.9)
Health Insurance status Yes
448 (78.5)
Donation status on driver’s license Yes
251 (42.9)
Note. Due to missing data, sample size (N) ranges from 569–585.
women were more likely than men to trust the healthcare system (p<.01), donation/allocation system (p<.01), and physicians (p<.01); to have more personal experiences with donation (p<.01); and to have more positive attitudes toward donation when compared to men (p<.05). Experiences with the donation/transplantation system was associated with attitudes toward donation (F [9,410] = 3.05, P<.01). Employment was also associated with attitudes toward donation; the mean was higher among VOL. 107, NO 3, SUMMER 2015 45
EXPLORING DONATION-RELATED KNOWLEDGE Table 2. Bivariate Associations between demographic variables and study variables
Independent Variables (Trust)
Dependent Variable
Healthcare System
Allocation System
Physician
Donation Beliefs & Attitudes
---
---
---
---
t = -3.09**
t = -2.97**
t = -2.42*
t = -2.69**
F(3,533)= 3.35*
---
---
F (3,419)= 11.52***
Employment Status
---
---
---
t = -2.35**
Household Income
---
---
---
---
Marital Status
---
---
---
---
Personal Experiences
---
---
---
F(9,410)= 3.05**
Age Gender Education
Note. *p<.05; **p<.01; ***p<.001; Empty cells are indicative of non-significant findings.
those were employed (M = 54.0) than among those who were unemployed [(M = 52.3), t(431) = -2.4, p<.05]. Educational attainment was also associated with both attitudes toward donation (F [3,483] = 13.99, p<.01) and trust in the healthcare system (F [3,533] = 3.47, p<.05). Finally, variables were entered into a regression model to determine the relationship between the types of trust and donation related beliefs and attitudes. Pearson correlations indicated an interrelationship exists among the trust variables such that trust in the healthcare system was related to both trust in the donation/allocation system (r = 0.59, p<.01) and physician trust (r = 0.21, p<.01); and
donation/allocation trust was correlated with physician trust (r = 0.35, p<.01). However, these correlations did not indicate concerns with multicollinearity.47 Thus, all assumptions of multiple linear regression were met except normality. Attitudes toward donation were nonnormally distributed, with skewness of 7.23 (SE =-0.53) and kurtosis = 0.15 (SE= 0.22). However, in accordance with the central limit theorem, given our large sample size, the sampling distribution of means is considered to be normally distributed regardless of the shape of the distributions of variables, as the F test is robust to violations of normality.48
Table 3. Trust regressed on Attitudes toward Donation
Trust Variable
Standardized Regression Coefficient (B) Model 1
Healthcare system Donation/allocation system
.03 -.07
Physician
.50***
Adjusted R2
.31
F
Model 2
25.97***
.09
Model 3 -
-
.11**
-
.09
8.84***
Model 4
.49***
.11 9.87***
.32 39.02***
Note. Models are adjusted for gender, educational attainment, employment, and personal experiences with donation. Model 1: Trust in healthcare system + Trust in donation/allocation system + Trust in physician + control variables Model 2: Trust in healthcare system + control variables Model 3: Trust in donation/allocation system + control variables Model 4: Trust in Physician + control variables *p<.05; **p<.01; ***p<.001.
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The attitudes toward donation variable was regressed upon four models: one with all three independent trust variables and confounding variables and three comprised of each trust variable (trust in the healthcare system, trust in donation/allocation system, and physician trust) individually, controlled only for confounding variables. Results indicate that in the full model, only physician level trust was significantly associated with attitudes toward donation (p<.001, see Table 3). The step-down models indicate that trust in the donation/allocation system (p<.01) and physician trust (p<.001) were both significantly associated with attitudes toward donation in the models in which they were the sole trust variable. Post-hoc Results. Our previous analyses demonstrated that physician trust and trust in the donation/allocation system were correlated (r = 0.35, p<.01). They also demonstrated that physician trust (β = 0.49; p = 0.00) and trust in the donation/allocation system (β = 0.11; p = 0.02) were each significantly associated with attitudes toward donation. Finally, the results had demonstrated that when attitudes toward donation were regressed upon both variables together, the association between trust in the donation/allocation system and attitudes toward donation became non-significant (β = -0.05; p = 0.32). Thus, a posthoc analysis was conducted to determine if physician trust is a mediating variable through which trust in the donation/allocation system is association with attitudes toward donation. A bias-corrected bootstrap confidence interval for indirect effects (10,000 bootstrap estimates) revealed a significant indirect effect of physician trust (B = 0.42, 95% CI = 0.26 to 0.58, see Table 4). There was no significant direct effect found on trust in the donation/
allocation system and attitudes toward donation when physician trust was in the model (B = -0.11, 95% CI = -0.35 to 0.13). In the presence of an indirect effect and absence of a direct effect, these results indicate that physician trust fully mediates the relationship between trust in the donation/allocation system and attitudes toward donation.
DISCUSSION AND CONCLUSION Prior research indicates that beliefs and attitudes about organ donation play a prominent role in disparities related to donor intention expression and behavior.38 It has also shown the impact of trust on willingness to donate and the expression of donation intentions,39,49 but exactly how trust impacts attitudes had not been explored. Using the conceptual model of trust of Hall et al.33 as a framework, this study sought to explore the relationship between trust and attitudes toward organ donation. Our findings indicate that varying dimensions of trust function differently in their influence on attitudes toward donation. Among the three trust variables, physician trust had the strongest relationship with attitudes toward donation and general trust in the healthcare system was not at all associated. Implications of these findings are discussed in the sections below. Trust and Attitudes toward Donation. The initial hypothesis that trust would be directly associated with positive attitudes toward donation was not supported across the three types of trust studied; trust in the healthcare system, trust in the donation/allocation system, and physician trust functioned differently. There was no association found between trust in the healthcare system and attitudes toward donation. This is surprising, given the degree to which the lack of equity in the healthcare system
Table 4. Post-hoc Mediation Analysis of testing Physician Trust as a mediator of the relationship between Trust in Donation/Allocation system and Attitudes toward Donation.
Trust Variable
Unstandardized Regression Coefficient (B) B
SE
t
p
95% CI
- 0.12
0.12
-0.91
0.34
-0.35, 0.12
Indirect Effect X on Y
0.42
.08
Z = 4.71
0.00***
0.26, 0.57
Total Effect X on Y
0.30
0.15
2.03
0.04*
0.01, 0.58
Direct Effect X on Y
Note. Models are adjusted for gender, educational attainment, employment, and personal experiences with donation. Y= Attitudes toward donation X= Trust in Donation/allocation M= Physician Trust *p<.05; **p<.01; ***p<.001.
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is studied and recognized as a significant barrier to the transplant and donation process.7,23,50–52 With regards to the healthcare system as a whole, for many AAs, it might be that there is a pervasive sense of distrust that extends far beyond organ donation. It is a deeply rooted, institutional level of distrust, one that is highlighted in the findings of Boulware et al.53 and Egede et al.,31 which not only has an overarching influence, but undermines multiple aspects of health-related behaviors. While this lack of trust is exemplified by historical accounts and daily experiences of prejudice and discrimination,15,54–56 these experiences may have less influence on the donation decision-making process. Organ donation is merely one small part of the overall healthcare system, thus one’s overall ambivalence toward this system may have very little impact on their specific attitudes toward donation. To the contrary, the level of trust that one has in relation to the donation/allocation system is, in fact, directly related to their attitudes towards organ donation; higher degrees of trust are associated with more positive attitudes. This relationship suggests the importance of differentiating the organ donation/allocation system from the umbrella of the entire healthcare system. It’s less likely that an average person would have many experiences with the donation/ allocation system; however, as one becomes more familiar with the specific practices, policies and ethics, this may impact attitudes toward donation and, thus, the expression of donation intentions. Physician trust was the strongest correlate observed and, in fact, had greater influence on attitudes toward donation than any of the other measured trust constructs. Moreover, it appears that physician trust behaves as a mediator and influences the degree to which one trusts in the donation allocation system and attitudes toward donation. This finding is critical within the realm of donation education, because it implies that those who are more trusting in their one-on-one relationships with physicians are more amendable to organ donation. It also speaks to the greater influence of personal medical relationships and experiences over those of a historical nature.57 While the historical injustices of Tuskegee and centuries of medical mistreatment are credited with creating an overwhelming sense of distrust of healthcare system, our research suggests that distrust may not be a generalized state of being among AAs. These findings highlight the relevance of physician trust and underline the need for a more tailored, individualized approach to promoting donationrelated behaviors. Because greater value is placed on physician-level interactions, an opportunity exists that can positively shape the degree of trust that one has in the donation/allocation system by counteracting some of the myths, misconceptions, and hearsay related to organ 48 VOL. 107, NO 3, SUMMER 2015
donation, and ultimately impact attitudes toward donation, donation intentions and behavior. Limitations. There are several issues that may limit the interpretation and application of our findings. This study utilized a convenience sample of AA participants within the southeastern United States. Because participants were recruited using CHAs, who recruited from their own social networks, they may have been more homogenous with respect to their thoughts and feelings regarding organ donation. By virtue of their willingness to participate, it might be that participants were generally more supportive of donation than those who did not agree to participate. However, the great variability in attitudes toward donation suggests that this was likely not the case (i.e., the data did not indicate overwhelming support for donation). Additionally, the overrepresentation of women and participants in a higher income bracket among our sample may have influenced the findings. Another potential limitation is that participants completed a self-administered survey and may have overestimated or underestimated their responses related to donation knowledge, beliefs, or attitudes (i.e. what participants said they are likely to do in this survey may differ from what they would actually do in real life). Lastly, the cross-sectional nature of our study in the ascertainment of varying types of trust and attitudes toward donation makes it impossible to distinguish cause and effect. Conclusion. Despite these limitations, our findings expand current understandings of the relationship between trust and attitudes toward donation. This research suggests that “trust” is not a monolithic variable, but may be more accurately described as having multiple facets that are differentially associated with attitudes toward donation. Frequently, the study and measurement of trust in research literature is broad, often incorporating several aspects of trust into a single variable. When these broad measures are used, the different nuances of trust are often lost. This study reveals that trust is multifaceted and should be measured with a multidimensional approach, particularly among racial/ethnic groups with complex histories with the healthcare system. Practice Implications. While previous research has found trust to be critical to donation decision-making,39 these findings provide a lens and explain the influence that different types of trust can have on attitudes toward donation. Moreover, our research has shown the pathway through which trust influences attitudes toward donation. However, additional research is needed to explore the direction of this association. It’s unclear as whether educating about the fairness of the donation/allocation improves attitudes toward donation or whether improving attitudes will help people to become more trusting of JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
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the donation/allocation system. Largely, our findings demonstrate that divergent experiences with distinct components of the healthcare system are differentially associated with attitudes toward donation. This study offers new direction and highlights the importance of continued research to further understand the complexities in shaping organ donation attitudes and behavior.
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2013, at http://www.minorityhealth.hhs.gov/.) 5. Weimer DL. Medical governance: Values, expertise, and interests in organ transplantation. Washington, D. C.: Georgetown University Press; 2010. 6. Why Minority Donors Are Needed. 2013. (Accessed August 19, 2013, at http://organdonor.gov/whydonate/minorities.html.) 7. Boulware LE, Ratner LE, Cooper LA, Sosa JA, LaVeist TA, Powe NR. Understanding disparities in donor behavior: Race and gender differences in willingness to donate blood and cadaveric organs. Medical Care 2002;40:85–94. 8. Callender CO, Miles PV, Hall MB, Gordon S. Blacks and whites and kidney transplantation: A disparity! but why and why won’t it go away? Transplantation Reviews 2002;16:163–76 9. Danovitch G, Cohen D, Weir M, et al. Current status of kidney and pancreas transplantation in the United States, 1994–2003. American Journal of Transplantation 2005;5:904–15. 10. Arriola KJ, Perryman JP, Doldren M. Moving beyond attitudinal barriers: understanding African Americans’ support for organ and tissue donation. Journal of the National Medical Association 2005;97:339–50. 11. Durand R, Decker PJ, Bruder P. Organ Donation among African Americans: Opportunities for Increasing Donor Rates. Hospital Topics 2002;80:34. 12. Minniefield WJ, Yang J, Muti P. Differences in attitudes toward organ donation among African Americans and whites in the United States. Journal of the National Medical Association 2001;93:372–9. 13. Morgan SE, Miller JK, Arasaratnam LA. Similarities and differences between African Americans’ and European Americans’ attitudes, knowledge, and willingness to communicate about organ donation. Journal of Applied Social Psychology 2003;33:693–715.
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21. Brandon DT, Issac LA, LaVeist TA. The Legacy of Tuskegee and Trust in Medical Care: Is Tuskegee Reponsible for Race Differences in Mistrust of Medical care. Journal of the National Medical Association 2005;97:951–6. 22. Morgan SE, Cannon T. African Americans’ knowledge about organ donation: Closing the gap with more effective perusasive message strategies. Journal of the National Medical Association 2003;95:1066–71. 23. Arriola KJ, Robinson DHZ, Perryman JP, Thompson N. Understanding the relationship between knowledge and African Americans’ donation decision-making. Patient Education and Counseling 2008;70:242–50. 24. Arriola KJ, Perryman JP, Doldren M.A., Warren CM, Robinson DHZ. Understanding the role of clergy in African American organ and tissue donation decision-making. Ethnicity and Health 2007;12:465–82. 25. Boulware LE, Troll MU, Wang NY, Powe N. R. Perceived Transparency and Fairness of the Organ Allocation System and Willingness to Donate Organs: A National Study. American Journal of Transplantation 2007;7:1778–87. 26. Kurz RS, Scharff DP, Terry T, Alexander S, Waterman A. Factors influencing organ donation decisions by African Americans: A review of the literature Medical Care Research and Review 2007;64:475–517. 27. Arriola KJ, Robinson DHZ, Boulware LE. Narrowing the gap between supply and demand of organs for transplantation. In: Braithwaite RL, Taylor SE, Treadwell HM, eds. Health Issues in the Black Community. 3rd ed. San Francisco: Jossey-Bass; 2009:157–76. 28. Petersen L. Racial differences in trust: Reaping what we have sown? Medical Care 2002;40:81–4.
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EXPLORING DONATION-RELATED KNOWLEDGE 29. Lee Y-Y, Lin JL. How much does trust really matter? A study of the longitudinal effect of trust and decision-making preferences on diabetic patient outcomes. Patient Education and Couseling 2011; Advance Online publication.
44. LaVeist TA, Nickerson KJ, Bowie JV. Attitudes about racism, medical mistrust, and satisfaction with care among African American and White cardiac patients. Medical Care Research and Review 2000;57:146–61.
30. Boulware LE, Cooper LA, Ratner LE, LaVeist TA, Powe NR. Race and trust in the health care system. Public Health Reports 2003;118:358–65.
45. McNamara P, Guadagnoli E, Evanisko MJ, et al. Correlates of support for organ donation among three ethnic groups Clinical Transplantation 1999;13.
31. Egede L, Ellis C. Development and testing of the multidimensional trust in health care systems scale. Journal of General Internal Medicine 2008;23:808–15.
46. Process Procedure for SPSS. 2014. (Accessed Setember 23, 2014, 2014, at http://www.afhayes.com/introduction-tomediation-moderation-and-conditional-process-analysis. html.)
32. Hall M.A., Dugan E, Zheng B, Mishra A. Trust in physicians and medical institutions: What is it, can it be measured, and does it matter? The Milbank Quarterly 2001;79:613–39. 33. Hall M.A., Camacho F, Dugan E, Balkrishnan R. Trust in the medical profession: conceptual and measurement issues. Health Services Resesarch 2002;37:1419–39. 34. Freburger J, Callahan L, Currey S, Anderson L. Use of the Trust in Physician Scale in patients with rheumatic disease: Psychometric properties and correlates of trust in the rheumatologist. Arthritis and Rheumatism 2003;49:51–8. 35. Dibben M, Morris S, Lean M. Situational trust and co-operative partnerships between physicians and their patients: a theoretical explanation transferable from business practice. Quarterly Journal of Medicine 2000;93:55–61. 36. Bussey-Jones J, Garrett J, Henderson G, Moloney M, Blumenthal C, Corbie-Smith G. The role of race and trust in tissue/blood donation for genetic research. Genetics in Medicine 2010;12:116–21. 37. Ajzen I. The theory of planned behavior. Organizational Behavior and Human Decision Processes 1991;50:179–211. 38. Wakefield CE, Watts KJ, Homewood J, Meiser B, Siminoff LA. Attitudes toward organ donation and donor behavior: a review of the international literature. Progress in Transplantation 2010;20:380–91. 39. Russell E, Robinson DHZ, Thompson N, Perryman JP, Arriola KJ. Distrust in the Healthcare System and Organ Donation Intentions Among African Americans. Journal of Community Health 2012;37:40–7. 40. Eng E, Parker E. Natural helper models to enhance a community’s health and competence. In: DiClemente R, Crosby R, Kegler M, eds. Emerging theories in health promotion practice and research San Francisco: Jossey-Bass; 2002:126–56. 41. DeJong W, Franz HG, Wolfe SM, et al. Requesting organ donation: An interview study of donor and nondonor families. American Journal of Critical Care 1998 7:13–23. 42. Rumsey S, Hurford DP, Cole AK. Influence of knowledge and religiousness on attitudes toward organ donation. Transplantation Proceedings 2003;35:2845–50. 43. Sander SL, Miller BK. Public knowledge and attitudes regarding organ and tissue donation: An analysis of the northwest Ohio community. Patient Education and Counseling 2005;58:154–63.
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47. Kleinbaum D, Kupper L, Muller K, Nizam A. Regression Diagnostics. Applied Regression Analysis and Other Multivariable Methods, 2nd Edition Pacific Grove: Thompson Brooks/Cole; 1998:206–27. 48. Tabachnick BG, Fidell LS. Cleaning up your act: Screening data prior to analysis. In: Rothman JL, ed. Using Multivariate Statistics, 2nd Ed. California State University, Northridge: Harper Collins; 1989:746. 49. McDonald EL, Powell CL, Perryman JP, Arriola KJ. Understanding the relationship between trust in health care and attitudes toward living donor transplant among African Americans with end-stage renal disease. Clinical Transplantation 2013;27:619–26. 50. Atkins L, Davis K, Holtzman SM, Durand R, Decker PJ. Family discussion about organ donation among African Americans. Progress in Transplantation 2003;13:28–32. 51. Callender CO, Hall MB, Branch D. An assessment of the effectiveness of the Mottep model for increasing donation rates and preventing the need for transplantation--adult findings: program years 1998 and 1999. Seminars in Nephrology 2001;21:419–28. 52. Davis K, Holtzman S, Durand R, Decker PJ, Zucha B, Atkins L. Leading the flock: Organ donation feelings, beliefs, and intentions among African American clergy and community residents. Progress in Transplantation 2005 15:211–6. 53. Boulware LE, Ratner LE, Sosa JA, Cooper LA, LaVeist TA, Powe NR. Determinants of willingness to donate living related and cadaveric organs: Identifying opportunities for intervention. Transplantation 2002;73:1683–91. 54. Shavers VL, Lynch CF, Burmeister LF. Factors that influence African-Americans’ willingness to participate in medical research studies. Cancer 2001;91. 55. Adegbembo AO, Tomar SL, Logan HL. Perception of racism explains the difference between Blacks and Whites level of healthcare trust. Ethnicity and Disease 2006;16:792–8. 56. Baker R. Minority distrust of medicine: A historical perspective. The Mount Sinai Journal of Medicine 1999;66:212–22. 57. Malat J, van Ryn M. African American preference for same-race healthcare professionals: The role of healthcare discrimination. Ethnicity and Disease 2005;15:740–7.
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Exploring Donation-related Knowledge, Attitudes, Beliefs and Distrust Among African Americans Dana HZ Robinson, M.P.H., Jennie P. Perryman, Ph.D., R.N., Nancy J. Thompson, Ph.D., M.P.H., C. Lamonte Powell, Ph.D., M.P.H., Kimberly R. Jacob Arriola, Ph.D., M.P.H.
Financial disclosures: We do not have any financial involvement with or financial interest with any organization or entity with a financial interest in this subject matter or materials disclosed in this manuscript. This research was supported by the National Institute of Diabetes and Digestive and Kidney Diseases (Grant 5 R01 DK79713-05). Abstract: Within the field of organ donation, multiple studies have shown differences in patterns of trust, however, it is unclear which elements are significantly related to donation decision making among African Americans. This study sought to disentangle the construct of trust by parceling out measures related to the healthcare system, the donation/allocation system, and the physician; and determine the relationship of these dimensions to attitudes toward organ and tissue donation. Cross-sectional survey data were gathered from 585 African American adults residing in the Atlanta metropolitan area. Results indicate that varying dimensions of trust function differently in their influence on attitudes toward donation. Our findings suggest that trust is critical to donation decision-making and should be measured with a multidimensional approach, particularly among racial/ ethnic groups with complex histories with the healthcare system. This study underlines the need for a more tailored, individualized approach to promoting organ and tissue donation among African Americans. Acknowledgements: We also thank Rianot Amzat, Mohua Basu and Rhonda DeLaremore for their assistance with data collection, cleaning, entry, and analysis.
Author Affiliations: Dana HZ Robinson, M.P.H., Rollins School of Public Health, Emory University; Jennie P Perryman, Ph.D., R.N., Emory Transplant Center, Emory Healthcare; Nancy J Thompson, Ph.D., M.P.H., Rollins School of Public Health, Emory University; C. Lamonte Powell, Ph.D., M.P.H., Rollins School of Public Health, Emory University; Kimberly R Jacob Arriola, Ph.D., M.P.H., Rollins School of Public Health of Emory University Correspondence: Dana H. Z. Robinson, Department of Behavioral Sciences and Health Education, Rollins School of Public Health of Emory University, 1518 Clifton Rd, Rm 521, Atlanta, GA 30322, Tel: (404) 727-2386, Fax: (404) 727-1369, [email protected]
INTRODUCTION
A
frican Americans (AAs) are disproportionately represented on the national transplant waiting list. While representing 13% of the U.S. population,1 AAs account for approximately 30% of the 123,000 transplant waitlist candidates.2 The need among AAs, in particular, is considerably high due to the disproportionate impact of certain health conditions (e.g., diabetes, hypertension, heart disease, hepatitis) that potentially warrant need for life-saving transplants. Nationally, the incidence rate of ESRD among AAs is 3.4 times greater than that among Whites.3 In the state of Georgia, where the present study was conducted, AAs comprise the majority of candidates on the kidney waiting list (63%) whereas nationally they represent a much smaller proportion of candidates (34.1%).2 African Americans are also overrepresented on the transplant waiting list, due in part, to the lack of 42 VOL. 107, NO 3, SUMMER 2015
histocompatible donors. The kidney matching process is heavily dependent on the similarity of ABO blood groups and protein complex HLA-human leukocyte antigens.4 Greater heterogeneity exists among AAs in their histocompatibility antigens compared to Whites; thus antigen-matched organs for AA patients are in greater demand.5 This difficulty is exacerbated by the underrepresentation of AAs in the donor pool and speaks to the necessity of increasing the number of potential AA donors.6 Negative attitudes towards donation play a prominent role in the lack of willingness among AAs to donate. Additional reasons for continuing lower donation rates include: (1) Lack of knowledge and awareness of the topic of donation and transplantation; (2) Religious myths, misperceptions and superstitions; (3) Fear of premature death; (4) Concerns about racism/classism and transplant system inequities; and (5) lack of trust in healthcare systems.7,8 Taken together, these factors contribute to AAs spending more than twice the amount of time on the national transplant waiting list compared to Whites.9 African American History of Distrust of the Healthcare System. Research suggests that a lack of trust in the health care system is an important factor in decisionmaking regarding organ donation.10–14 This overarching sense of distrust also expands to influencing care-seeking behavior,15–17 undermines participation in research,18,19 and even influences the signing of living wills.20 Patterns of negative interactions with the healthcare system21 coupled with centuries of exploitation by the medical establishment have laid a foundation for a pervasive sense of distrust.15 Trust and Attitudes related to Organ Donation. Concerns about race and class-based inequalities are severe limiting factors with respect to organ donation.23 While this reluctance, in part, may be due to a lack of understanding of how the process of organ donation and transplantation works,24 genuine fears of discrimination and exploitation have perpetuated overall feelings of distrust of the medical establishment. Concerns have been raised about the fairness of the organ allocation system such that many feel that they will not receive the same quality of care as Whites25 and others feel that consenting JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
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to donation might hasten death.26 These misgivings associated with the field of medicine and equity within the healthcare systems influence attitudes about organ donation and subsequently affect the rates at which people are willing to become organ donors.27 Barriers to donation for the AA population are welldocumented but not necessarily well understood. Thus, research in this area is necessary for the development of culturally-sensitive interventions that shape AAs’ attitudes and donation intentions. Measuring Trust. In the literature, trust is widely acknowledged as an essential component in health-related interactions. Research has found that trust is fundamental in patient satisfaction, adherence to prescribed medical advice, as well as positive health outcomes.28,29 Multiple dimensions of trust have also been identified in relation to the different components of the healthcare system.30–32 Divergent experiences may result in varying levels of trust and, therefore, warrant a multidimensional approach. The trust that one has in his/her physician may differ from trust in hospitals, as well as in private or government entities. It is suggested that these varying interactions can be categorized into two distinct aspects of trust: (1) interpersonal/physician and (2) system/social trust. Interpersonal trust is developed over time and based on individual experiences with a provider.30–32 Conversely, system/social trust is often referenced by past experiences, general impressions, societal views, and second-hand interactions with professional health and medical institutions.30–32 Despite extensive research into the role of trust, there has been very little effort to systematically explore trust as a pathway and/or its interrelationships with attitudes in shaping donation-related behavior. While, explanatory models that explore trust and other constructs that shape attitudes toward organ donation are scarce, one notable exception is a conceptual model of trust in the medical profession, proposed by Hall et al.33 In this model, the authors posit that general trust (characterized by attitudes toward a broader, social, professional medical system) and physician trust are related measures but differ significantly in their influence on certain patient attitudes and behaviors.33 Previously this model was used in a clinical setting in the context of patient satisfaction with care and willingness to adhere to recommendations; however, it is our purpose to expand this model for use in the context of organ donation. Within the field of donation, multiple studies have shown differences in patterns of trust.17,30,32,34,35 However, it is unclear which elements are significantly related to donation decision making among AAs. The construct of trust has numerous components and most studies that address organ donation behavior use a single trust JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
scale that is composed of a conglomerate of items.12,14,36 Oftentimes these items muddle the different dimensions of trust. The proposed study makes novel contributions to the field of donation by disentangling and creating a deeper understanding of this concept of trust. From a theoretical perspective, the relationship between attitudes and behavior has been widely studied.37 Specifically, organ donation beliefs and attitudes have been reported as significant predictors of both willingness to donate and the expression of donation intentions.38 Trust is equally important and has also been studied extensively with regards to its influence on donation behavior.24,39 Both of these core components are integral to the donation decision making process, however, the degree to which they influence one another has yet to be explored. The purpose of this study was to modify the Hall et al.33 conceptual model of trust and increase its cultural relevance to AAs by exploring the relationship between trust and attitudes toward donation. This adapted model incorporates a broader measurement of trust and differentiates among three types of trust. We distinguished between physician trust and two types of system-level trust (healthcare system and donation/allocation system) and investigated how these constructs are related to attitudes toward organ donation. This study was guided by the following hypotheses: 1. Trust in the healthcare system is associated with positive attitudes toward donation. 2. Trust in the donation/allocation system is associated with positive attitudes toward donation. 3. Physician trust is associated with positive attitudes toward donation.
METHODS Study Design. The present study is part of a larger study testing the effectiveness of a culturally-sensitive organ donation intervention for AA adults. The parent study uses a randomized, pre-post design with a control group; data from the current study were collected during the baseline assessment (March to December 2009). Using a crosssectional research design, the current study combined baseline data from both intervention and control groups. Community Health Advocates & Participant Recruitment. Community Health Advocates (CHAs40) facilitated participant recruitment. There were a total of 19 CHAs selected based on their demographic similarity to our target population and their ability to bring together a variety of people. Each CHA was trained and tasked with recruiting a total of 32 participants into the study from members of their social networks (church, professional or community affiliations, family, friends, and associates). Each CHA hosted multiple group educational sessions in which participants watched a video, engaged VOL. 107, NO 3, SUMMER 2015 43
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in group discussion and completed a questionnaire. Group sessions were conducted in a comfortable environment at either the CHA’s home or at a private location in the community (e.g., community center, library, church, fire station community room). Participants were recruited with the understanding that they were participating in a two-hour, group, health-related discussion and would be compensated $15 in appreciation for their time. Participants were considered eligible if they selfidentified as Black or AA (for the purpose of this study, the term “Black” includes people of African descent, regardless of cultural identification) and were 18 years of age or older. Prospective participants read and signed the consent form and completed the baseline questionnaire independently. This study was conducted with University Institutional Review Board approval. Measures. Participants completed a survey that included measures of attitudes/beliefs regarding donation and transplantation; healthcare, donation/allocation systems, and physician-level trust; and demographic characteristics. A total of four scales were used. Below are descriptions of each individual scale: Attitudes and beliefs toward organ donation/ transplantation were captured using a 13-item scale.41–43 This scale included items that measured support for and concerns about donation such as “organ donation is a cause worth supporting” and “I believe it’s important for a person to have all of their parts when buried”. Response options for these items ranged from 1 (strongly disagree) to 5 (strongly agree); higher scores indicated more positive attitudes towards organ donation, and total scores ranged from 25 to 65 (M=53.3, SD=7.2; α =.86). Trust in the healthcare system was measured using a 5-item scale.44 This scale examined participants’ attitudes regarding the existence of discrimination and racism within the healthcare setting using items such as, “patients have sometimes been deceived or misled at hospitals” and “hospitals have sometimes done harmful experiments on patients without their knowledge.” Participants were asked to indicate their agreement with the statements using a 5-point scale ranging from 1 (strongly disagree) to 5 (strongly agree), higher scores indicated more trust of the healthcare system, and scores ranged from 5 to 25 (M=14.1, SD=3.3; α=.72). Trust in the organ donation/allocation system was measured using a 4-item scale, adapted from previously developed scales43,45 that specifically addressed aspects of discrimination and economic equity in the organ donation/allocation system. Sample items included, “racial discrimination prevents minority patients from receiving organ transplants they need” and “organs can be bought and sold on the black market in the United States.” In this 44 VOL. 107, NO 3, SUMMER 2015
study, participants indicated their level of agreement from “strongly disagree” to “strongly agree,” and scores ranged from 5 to 20 (M=12.8, SD=2.8; α =.61), with higher scores indicating more trust in the donation/allocation system. Physician trust was measured using a 3-item scale.42 This scale examines the level of trust that participants specifically have in physicians. It addresses issues of trust with regards to organ donation such as, “I think that doctors would try just as hard to save my life whether or not I plan to be an organ donor.” In this study, response choices ranged from strongly disagree to strongly agree on a 5-point, Likert scale with scores ranging from 3 to 15 (M=11.6, SD=2.1; α =.70), such that higher scores indicated more trust in one’s physician. Demographic Characteristics included measures of age, gender, educational attainment, employment, income, marital status and personal experiences with donation. The personal experiences with donation scale captured whether people were personally impacted by the donation system. On this scale, respondents were asked to respond ‘‘yes’’ or ‘‘no’’ to nine author-created items such as ‘‘I know someone who donated an organ while living,’’ and ‘‘I know someone who received an organ transplant.’’ Respondents’ scores represent the number of items to which they responded favorably. Since the scale did not seek to measure a one-dimensional construct, no effort was made to demonstrate internal consistency of the items. Statistical Analyses. Participant demographic characteristics were first analyzed using descriptive statistics, then analyzed in relation to each study variable in the model. Pearson correlations were used to explore the relationship between age and the continuous variables to be included in the model (i.e., trust in the healthcare system, trust in the organ allocation system, physician trust, and attitudes toward donation). One-way Analyses of Variance (ANOVA) were used to determine the associations between the categorical variables education, income, and personal experiences with donation and continuous variables cited above. T-tests were used to explore associations between dichotomous variables of gender, marital status, and employment and continuous variables cited above. Based on significant bivariate findings, those variables that were related to one of the trust variables (predictor variables) and/or the outcome variable of beliefs/attitudes were entered into the regression model. Next, an ANOVA was conducted to address the possibility of nesting and determine whether participants recruited by a given CHA held more donation beliefs that were more similar to each other compared to participants who were recruited by another CHA. First, we created a dummy variable for “CHA” to use as the independent variable. Next, we conducted an ANOVA to test whether JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
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between-CHA variability in donation beliefs (across CHAs) was greater than within-CHA variability in donation beliefs (within a CHA group). Results from this analysis were not significant (p=.29); therefore, we did not control for CHA in the regression model. A series of multiple linear regressions were conducted to assess the relationship between each of the trust variables and attitudes toward donation. We present a full model that includes all three trust variables and then three stepdown models that explore the independent relationship of each of the variables to dependent variable. All models control for educational attainment, gender, employment and personal experiences with donation. An α of .05 was used to determine statistical significance. Post-hoc Analyses. A mediation analysis was conducted using the macros PROCESS Procedure for SPSS46 in order to better understand the relationship between trust in the donation/allocation system, physician trust, and attitudes toward donation. The PROCESS macro was chosen for its ability to compute the indirect effect by calculating the product of coefficients. The custom dialog file was installed in SPSS and linear regression was conducted between trust in the donation/allocation system, physician trust, and attitudes toward donation. All models controlled for educational attainment, gender, employment and personal experiences with donation. An α of .05 was used to determine statistical significance.
RESULTS Description of Study Participants. At baseline, a total of 585 participants completed the survey, the majority of whom were female (69%; see Table 1). Similar proportions of the sample reported that their highest level of educational attainment was high school (39%) or college (42%). Similar proportions of participants also reported being single/never married (37%) and married (39%). Participants tended to report working full or part time (63%), the majority had health insurance (78%) and ages ranged from 19 to 96 years (M=46.3, SD=14.6). About one-third of participants were recognized as donors on their driver’s licenses. Participants held positive attitudes toward donation (M=53.2, SD=7.2), and had minimal personal experiences with the organ donation/transplantation system (M=2.9, SD=2.1). Bivariate and Regression Analyses. The next analyses explored the demographic variables in relationship to each of the study variables to determine whether they would be included in the regression model (see Table 2). Age was not related to attitudes toward donation (r = .03, p>.05) or any of the trust variables [healthcare system (r = .05, p>.05), donation/allocation system (r =.03, p>.05), physician trust (r = .02, p>.05)]. Gender was significantly related to all of the study variables, such that JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
Table 1. Demographic Characteristics of Study Participants (N=585)
Characteristic
N (%)
Mean age in years (range)
46.2 (19–96)
Female
398 (69.2)
Race/Ethnicity Black/African American
499 (87.1)
Black/Caribbean
52 (9.1)
Black/Hispanic
9 (1.6)
Other
13 (2.2)
Educational Attainment Less than high school
29 (5.1)
High school graduate or GED
224 (39.4)
Completed college
237 (41.7)
Professional degree
79 (13.9)
Employment status Unemployed
118 (20.9)
Retired
91 (16.0)
Working part or full time
361 (63.3)
Marital status never married
208 (36.9)
married
225 (39.2)
divorced/separated/widowed
115 (23.9)
Health Insurance status Yes
448 (78.5)
Donation status on driver’s license Yes
251 (42.9)
Note. Due to missing data, sample size (N) ranges from 569–585.
women were more likely than men to trust the healthcare system (p<.01), donation/allocation system (p<.01), and physicians (p<.01); to have more personal experiences with donation (p<.01); and to have more positive attitudes toward donation when compared to men (p<.05). Experiences with the donation/transplantation system was associated with attitudes toward donation (F [9,410] = 3.05, P<.01). Employment was also associated with attitudes toward donation; the mean was higher among VOL. 107, NO 3, SUMMER 2015 45
EXPLORING DONATION-RELATED KNOWLEDGE Table 2. Bivariate Associations between demographic variables and study variables
Independent Variables (Trust)
Dependent Variable
Healthcare System
Allocation System
Physician
Donation Beliefs & Attitudes
---
---
---
---
t = -3.09**
t = -2.97**
t = -2.42*
t = -2.69**
F(3,533)= 3.35*
---
---
F (3,419)= 11.52***
Employment Status
---
---
---
t = -2.35**
Household Income
---
---
---
---
Marital Status
---
---
---
---
Personal Experiences
---
---
---
F(9,410)= 3.05**
Age Gender Education
Note. *p<.05; **p<.01; ***p<.001; Empty cells are indicative of non-significant findings.
those were employed (M = 54.0) than among those who were unemployed [(M = 52.3), t(431) = -2.4, p<.05]. Educational attainment was also associated with both attitudes toward donation (F [3,483] = 13.99, p<.01) and trust in the healthcare system (F [3,533] = 3.47, p<.05). Finally, variables were entered into a regression model to determine the relationship between the types of trust and donation related beliefs and attitudes. Pearson correlations indicated an interrelationship exists among the trust variables such that trust in the healthcare system was related to both trust in the donation/allocation system (r = 0.59, p<.01) and physician trust (r = 0.21, p<.01); and
donation/allocation trust was correlated with physician trust (r = 0.35, p<.01). However, these correlations did not indicate concerns with multicollinearity.47 Thus, all assumptions of multiple linear regression were met except normality. Attitudes toward donation were nonnormally distributed, with skewness of 7.23 (SE =-0.53) and kurtosis = 0.15 (SE= 0.22). However, in accordance with the central limit theorem, given our large sample size, the sampling distribution of means is considered to be normally distributed regardless of the shape of the distributions of variables, as the F test is robust to violations of normality.48
Table 3. Trust regressed on Attitudes toward Donation
Trust Variable
Standardized Regression Coefficient (B) Model 1
Healthcare system Donation/allocation system
.03 -.07
Physician
.50***
Adjusted R2
.31
F
Model 2
25.97***
.09
Model 3 -
-
.11**
-
.09
8.84***
Model 4
.49***
.11 9.87***
.32 39.02***
Note. Models are adjusted for gender, educational attainment, employment, and personal experiences with donation. Model 1: Trust in healthcare system + Trust in donation/allocation system + Trust in physician + control variables Model 2: Trust in healthcare system + control variables Model 3: Trust in donation/allocation system + control variables Model 4: Trust in Physician + control variables *p<.05; **p<.01; ***p<.001.
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The attitudes toward donation variable was regressed upon four models: one with all three independent trust variables and confounding variables and three comprised of each trust variable (trust in the healthcare system, trust in donation/allocation system, and physician trust) individually, controlled only for confounding variables. Results indicate that in the full model, only physician level trust was significantly associated with attitudes toward donation (p<.001, see Table 3). The step-down models indicate that trust in the donation/allocation system (p<.01) and physician trust (p<.001) were both significantly associated with attitudes toward donation in the models in which they were the sole trust variable. Post-hoc Results. Our previous analyses demonstrated that physician trust and trust in the donation/allocation system were correlated (r = 0.35, p<.01). They also demonstrated that physician trust (β = 0.49; p = 0.00) and trust in the donation/allocation system (β = 0.11; p = 0.02) were each significantly associated with attitudes toward donation. Finally, the results had demonstrated that when attitudes toward donation were regressed upon both variables together, the association between trust in the donation/allocation system and attitudes toward donation became non-significant (β = -0.05; p = 0.32). Thus, a posthoc analysis was conducted to determine if physician trust is a mediating variable through which trust in the donation/allocation system is association with attitudes toward donation. A bias-corrected bootstrap confidence interval for indirect effects (10,000 bootstrap estimates) revealed a significant indirect effect of physician trust (B = 0.42, 95% CI = 0.26 to 0.58, see Table 4). There was no significant direct effect found on trust in the donation/
allocation system and attitudes toward donation when physician trust was in the model (B = -0.11, 95% CI = -0.35 to 0.13). In the presence of an indirect effect and absence of a direct effect, these results indicate that physician trust fully mediates the relationship between trust in the donation/allocation system and attitudes toward donation.
DISCUSSION AND CONCLUSION Prior research indicates that beliefs and attitudes about organ donation play a prominent role in disparities related to donor intention expression and behavior.38 It has also shown the impact of trust on willingness to donate and the expression of donation intentions,39,49 but exactly how trust impacts attitudes had not been explored. Using the conceptual model of trust of Hall et al.33 as a framework, this study sought to explore the relationship between trust and attitudes toward organ donation. Our findings indicate that varying dimensions of trust function differently in their influence on attitudes toward donation. Among the three trust variables, physician trust had the strongest relationship with attitudes toward donation and general trust in the healthcare system was not at all associated. Implications of these findings are discussed in the sections below. Trust and Attitudes toward Donation. The initial hypothesis that trust would be directly associated with positive attitudes toward donation was not supported across the three types of trust studied; trust in the healthcare system, trust in the donation/allocation system, and physician trust functioned differently. There was no association found between trust in the healthcare system and attitudes toward donation. This is surprising, given the degree to which the lack of equity in the healthcare system
Table 4. Post-hoc Mediation Analysis of testing Physician Trust as a mediator of the relationship between Trust in Donation/Allocation system and Attitudes toward Donation.
Trust Variable
Unstandardized Regression Coefficient (B) B
SE
t
p
95% CI
- 0.12
0.12
-0.91
0.34
-0.35, 0.12
Indirect Effect X on Y
0.42
.08
Z = 4.71
0.00***
0.26, 0.57
Total Effect X on Y
0.30
0.15
2.03
0.04*
0.01, 0.58
Direct Effect X on Y
Note. Models are adjusted for gender, educational attainment, employment, and personal experiences with donation. Y= Attitudes toward donation X= Trust in Donation/allocation M= Physician Trust *p<.05; **p<.01; ***p<.001.
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is studied and recognized as a significant barrier to the transplant and donation process.7,23,50–52 With regards to the healthcare system as a whole, for many AAs, it might be that there is a pervasive sense of distrust that extends far beyond organ donation. It is a deeply rooted, institutional level of distrust, one that is highlighted in the findings of Boulware et al.53 and Egede et al.,31 which not only has an overarching influence, but undermines multiple aspects of health-related behaviors. While this lack of trust is exemplified by historical accounts and daily experiences of prejudice and discrimination,15,54–56 these experiences may have less influence on the donation decision-making process. Organ donation is merely one small part of the overall healthcare system, thus one’s overall ambivalence toward this system may have very little impact on their specific attitudes toward donation. To the contrary, the level of trust that one has in relation to the donation/allocation system is, in fact, directly related to their attitudes towards organ donation; higher degrees of trust are associated with more positive attitudes. This relationship suggests the importance of differentiating the organ donation/allocation system from the umbrella of the entire healthcare system. It’s less likely that an average person would have many experiences with the donation/ allocation system; however, as one becomes more familiar with the specific practices, policies and ethics, this may impact attitudes toward donation and, thus, the expression of donation intentions. Physician trust was the strongest correlate observed and, in fact, had greater influence on attitudes toward donation than any of the other measured trust constructs. Moreover, it appears that physician trust behaves as a mediator and influences the degree to which one trusts in the donation allocation system and attitudes toward donation. This finding is critical within the realm of donation education, because it implies that those who are more trusting in their one-on-one relationships with physicians are more amendable to organ donation. It also speaks to the greater influence of personal medical relationships and experiences over those of a historical nature.57 While the historical injustices of Tuskegee and centuries of medical mistreatment are credited with creating an overwhelming sense of distrust of healthcare system, our research suggests that distrust may not be a generalized state of being among AAs. These findings highlight the relevance of physician trust and underline the need for a more tailored, individualized approach to promoting donationrelated behaviors. Because greater value is placed on physician-level interactions, an opportunity exists that can positively shape the degree of trust that one has in the donation/allocation system by counteracting some of the myths, misconceptions, and hearsay related to organ 48 VOL. 107, NO 3, SUMMER 2015
donation, and ultimately impact attitudes toward donation, donation intentions and behavior. Limitations. There are several issues that may limit the interpretation and application of our findings. This study utilized a convenience sample of AA participants within the southeastern United States. Because participants were recruited using CHAs, who recruited from their own social networks, they may have been more homogenous with respect to their thoughts and feelings regarding organ donation. By virtue of their willingness to participate, it might be that participants were generally more supportive of donation than those who did not agree to participate. However, the great variability in attitudes toward donation suggests that this was likely not the case (i.e., the data did not indicate overwhelming support for donation). Additionally, the overrepresentation of women and participants in a higher income bracket among our sample may have influenced the findings. Another potential limitation is that participants completed a self-administered survey and may have overestimated or underestimated their responses related to donation knowledge, beliefs, or attitudes (i.e. what participants said they are likely to do in this survey may differ from what they would actually do in real life). Lastly, the cross-sectional nature of our study in the ascertainment of varying types of trust and attitudes toward donation makes it impossible to distinguish cause and effect. Conclusion. Despite these limitations, our findings expand current understandings of the relationship between trust and attitudes toward donation. This research suggests that “trust” is not a monolithic variable, but may be more accurately described as having multiple facets that are differentially associated with attitudes toward donation. Frequently, the study and measurement of trust in research literature is broad, often incorporating several aspects of trust into a single variable. When these broad measures are used, the different nuances of trust are often lost. This study reveals that trust is multifaceted and should be measured with a multidimensional approach, particularly among racial/ethnic groups with complex histories with the healthcare system. Practice Implications. While previous research has found trust to be critical to donation decision-making,39 these findings provide a lens and explain the influence that different types of trust can have on attitudes toward donation. Moreover, our research has shown the pathway through which trust influences attitudes toward donation. However, additional research is needed to explore the direction of this association. It’s unclear as whether educating about the fairness of the donation/allocation improves attitudes toward donation or whether improving attitudes will help people to become more trusting of JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION
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the donation/allocation system. Largely, our findings demonstrate that divergent experiences with distinct components of the healthcare system are differentially associated with attitudes toward donation. This study offers new direction and highlights the importance of continued research to further understand the complexities in shaping organ donation attitudes and behavior.
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