Knowledge, attitudes, and self-efficacy toward cancer genetic testing among Black women with and without breast cancer

Abstract

Objective

To assess knowledge and attitudes regarding cancer genetic testing among Black women with and without breast cancer and to identify individual-level predictors of these outcomes.

Methods

Participants were 927 women who completed a questionnaire about personal and family history of cancer; prior hereditary cancer genetic testing; and cancer genetics knowledge, attitudes, and self-efficacy. Linear regression was used to examine predictors of cancer genetics knowledge, attitudes, and self-efficacy.

Results

Knowledge scores did not differ between women who had a history of breast cancer (mean, 12.5/16; SD 2.4) and those who did not (mean, 12.3; SD, 2.4). The majority of women answered most questions correctly; however, incorrect responses were common for questions about inherited cancer etiology (34% answered incorrectly), test limitations (44%), and clinical implications of a variant of uncertain significance (71%). Personal breast cancer history was associated with more favorable attitudes but not self-efficacy. Significant predictors of knowledge, attitudes, or self-efficacy included age, educational attainment, and marital status.

Conclusions

Overall knowledge, attitudes, and self-efficacy regarding cancer genetic testing were high among U.S. Black women regardless of prior breast cancer, though educational gaps remain.

Introduction

Racial disparities in cancer mortality persist, with Black men and women experiencing higher mortality than White men and women, despite similar or lower incidence [1]. For breast cancer, the most common cancer in women across all racial/ethnic groups, mortality rates are nearly 40% higher among Black women compared to white women [2]. Differences in perceived cancer risk by race and ethnicity have also been reported, with some studies suggesting that a substantial proportion of Black men and women may underestimate their personal risk [3–8]. Individuals who perceive their cancer risk as low may be less likely to engage in risk-reducing behaviors [9]. Thus, improving cancer outcomes for Black populations may necessitate efforts to heighten the awareness of personal risk.

Germline genetic testing for hereditary cancer risk offers opportunities for clinical decision-making about screening and risk management for individuals and their family members. Despite the availability of cancer genetic testing, Black individuals are still much less likely to receive or engage with testing compared to non-Hispanic White individuals [10–13], even when referred for testing [10]. System- and provider-level factors, such as access to specialists, clinical workflows, and biases in physician referral practices, contribute to this disparity [12, 14, 15]. Individual-level and sociocultural factors such as medical mistrust and concerns about genetic discrimination may also contribute to lower acceptance of genetic counseling and testing engagement [13]. Limited awareness about the availability of testing and knowledge gaps in understanding general concepts of inheritance, personal hereditary cancer risk, and interpretation of test results may also play a role. In prior research, perceived benefits were strongly associated with intent to test [16–18], highlighting the importance of individual-level beliefs and attitudes in decisions about genetic testing.

Relatively few studies have evaluated cancer genetic knowledge among Black individuals, and those that have generally focused on high-risk populations, such as breast cancer patients or those with a strong family history of cancer [19–22]. To our knowledge, no prior studies have examined levels of knowledge or attitudes toward cancer genetic testing in a Black population with a broad range of risk profiles. Identifying knowledge gaps and predictors of knowledge are essential to informing educational strategies to improve genetic testing opportunities for all populations. Therefore, we sought to measure knowledge about and attitudes toward cancer genetic testing as well as genetics self-efficacy (i.e., confidence in one’s ability to use genetic information) among Black women with and without breast cancer and to identify individual-level factors influencing these constructs.

Methods

Study population

This study was part of a randomized controlled trial of alternate disclosure modalities for returning individual-level cancer genetic research results embedded in the Black Women’s Health Study (BWHS). The parent cohort was established in 1995 among respondents to a mailed questionnaire sent to subscribers of Essence magazine and members of selected Black professional organizations; other than age (restricted to ages 21–69), there were no other selection criteria [23]. A subset of BWHS participants were subsequently recruited to participate in the current study; details of the trial eligibility and design have been reported elsewhere [24]. In brief, BWHS participants with and without breast cancer whose DNA samples had been sequenced as part of a nested case–control study on the genetic etiology of breast cancer (1325 cases; 2871 controls) [25, 26] were eligible for the trial if they were still living, not lost to follow-up, and without known cognitive impairment. Women were ineligible if the research testing had identified a variant of uncertain significance in the absence of a pathogenic or likely pathogenic variant. Among 2670 eligible women invited to enroll in the trial, 927 (35%) consented and completed a baseline questionnaire in 2023 and early 2024.

Data collection

All women in the present study completed a baseline questionnaire about personal and family history of cancer; prior clinical genetic testing for hereditary cancer; and knowledge about cancer genetics and testing, attitudes toward testing, and genetics self-efficacy. Knowledge was measured as the sum of correct answers to 16 true/false statements to assess factual understanding of genetics, genetic risk of cancer, inheritance, and clinical and legal implications of genetic testing. These 16 true/false statements (see Fig. 1) were adapted from existing measures of cancer genetic knowledge [18, 27–31]. Missing responses were coded as incorrect. Higher scores indicate greater knowledge. Attitudes toward genetic testing were assessed as perceptions of benefits of genetic testing, using a 3-item scale adapted from prior work [18]. Items such as “Genetic testing will help me manage my cancer risk” were rated from 1=“strongly disagree” to 5=“strongly agree,” with higher score indicating more favorable attitudes (Cronbach’s alpha, 0.74). Finally, genetics self-efficacy was assessed using an adapted 4-item scale [32], reflecting one’s confidence in their ability to use genetic information, measured as the mean score of four 5-point Likert-scale items, such as “I have a good idea about how genetics may influence risk for disease generally.” Again, higher score indicates greater self-efficacy (Cronbach’s alpha, 0.79).

Fig. 1.

Cancer genetics knowledge by breast cancer history. The percentage of participants with (black bar) and without breast cancer (gray bar) who answered each of 16 true/false statements about cancer genetics correctly

Information on demographic and other individual-level factors was available from biennial BWHS questionnaires, beginning in 1995. Specifically, educational attainment was assessed in 1995 and updated in 2003; marital status was assessed most recently in 2005.

Statistical analyses

We calculated mean knowledge, attitudes, and self-efficacy scores among women with and without breast cancer and used multivariable linear regression to evaluate the association of individual-level factors, including age, educational attainment, marital status, personal history of breast or other cancer, first-degree family history of breast cancer (i.e., diagnosis in a biological mother, father, sister, brother, daughter, or son), and prior genetic testing for cancer with each of these constructs. Linear regression models estimated beta-coefficients (expected difference in means) and 95% confidence intervals comparing knowledge, attitudes, or self-efficacy measures across groups. For each knowledge item, we also report the percent of women with correct responses according to personal history of breast cancer.

This study was approved by the Institutional Review Board of the Boston University Medical Campus. All participants provided written informed consent at enrollment in the parent trial.

Results

Participant characteristics. Because we enrolled participants who had been selected for a nested case–control study of breast cancer, nearly one-third of participants (n=273, 29%) had a personal history of breast cancer. Mean age was 67.5 years among women with breast cancer and 66.4 years among women without breast cancer. Educational attainment was high in both groups with >65% reporting having earned a college or higher degree. A large majority (98%) of participants had health insurance. Women with breast cancer were somewhat less likely to have never married compared to those without breast cancer (17% vs. 22% among those with non-missing data). Women with breast cancer were more likely than those without breast cancer to have a personal history of other cancer (5.1% vs. 3.2%) or a first-degree family history of breast cancer (31.9% vs. 19.3%). They were much more likely to report having had prior genetic testing for cancer (39.9% vs. 3.7%) (Table 1).

Table 1.

Characteristics of the study population, by breast cancer history (n=927)

	No personal history of breast cancer	Personal history of breast cancer
	N=654	N=273
Age, years (mean)	66.4 (8.4)	67.5 (8.8)
Educational attainment
≤ 12 years	59 (9.0)	31 (11.4)
13–15 years	154 (23.6)	52 (19.0)
16 years	170 (26.0)	86 (31.5)
≥ 17 years	271 (41.4)	104 (38.1)
Health insurance status
Insured	639 (97.7)	268 (98.2)
Uninsured	11 (1.7)	3 (1.1)
Don’t know/missing	4 (0.6)	2 (0.7)
Marital status
Married/living as married	278 (42.5)	122 (44.7)
Separated/divorced/widowed	199 (30.4)	79 (28.9)
Never married	134 (20.5)	42 (15.8)
Missing	43 (6.6)	29 (10.6)
Personal history of any other cancer	21 (3.2)	14 (5.1)
First-degree family history of breast cancer	126 (19.3)	87 (31.9)
Ever had a cancer genetic test
Yes	24 (3.7)	109 (39.9)
No	604 (92.4)	132 (48.4)
Don’t know/missing	26 (4.0)	32 (11.0)

Means (standard deviation) or counts (percent) are presented

Knowledge. Overall, mean knowledge score was 12.4 out of 16 (77%). There were no differences in knowledge score between women who had a personal history of breast cancer (mean score 12.5; SD 2.4) and those who did not (mean score 12.3; SD 2.4). Thirteen of the sixteen knowledge questions were answered correctly by at least 70% of participants; however, participants were less likely to correctly answer questions about the inherited genetic etiology of cancer, limitations of genetic testing, and clinical implications of a variant of uncertain significance. Specifically, among women with and without breast cancer, 72.9% and 62.8%, respectively, correctly indicated “false” to the statement “Most cancer is caused by inherited gene mutations;” 57.1% and 56% correctly indicated “false” to the statement “A genetic test can always determine if an individual has a cancer gene mutation;” and 31.5% and 27.4% correctly indicated “false” to the statement “A Variant of Uncertain Significance (VUS) will usually influence cancer screening recommendations” (Fig. 1).

In multivariable-adjusted models, younger age, higher educational attainment, being married, and having had prior genetic testing were statistically significant predictors of higher total knowledge score. Specifically, mean knowledge scores decreased by 0.5 points (95% CI −0.7, −0.3) for every 10-year increase in age. Mean knowledge scores increased with increasing educational attainment: compared to women with ≤12 years of education, those with ≥17 years had scores that were 1.7 points higher (95% CI: 1.18, 2.21). Women who were separated, divorced, or widowed had somewhat lower scores than those who were married or living as married (β: −0.44; 95% CI: −0.78, −0.09). Having had prior cancer genetic testing was associated with higher knowledge scores (β: 0.66; 95% CI: 0.17, 1.15). There were no differences in mean knowledge scores by first-degree family history of breast cancer or personal history of breast or other cancer (Table 2).

Table 2.

Predictors of total knowledge, attitude, and self-efficacy scores*

Age, per 10 years	Knowledge β (95% CI)	Attitude β (95% CI)	Self-efficacy β (95% CI)
	−0.53 (−0.72, −0.35)	−0.08 (− 0.14, −0.03)	−0.05 (−0.11, 0.00)
Educational attainment
≤ 12 years	Reference	Reference	Reference
13–15 years	0.78 (0.23, 1.33)	0.19 (0.03, 0.35)	0.28 (0.11, 0.44)
16 years	1.25 (0.71, 1.79)	0.11 (−0.05, 0.27)	0.29 (0.12, 0.45)
≥ 17 years	1.70 (1.18, 2.21)	0.12 (−0.03, 0.27)	0.31 (0.15, 0.47)
Marital status
Married/living as married	Reference	Reference	Reference
Separated/divorced/widowed	−0.44 (− 0.78, −0.09)	0.00 (−0.09, 0.10)	0.01 (−0.09, 0.11)
Never married	−0.30 (− 0.70, 0.10)	−0.16 (−0.28, −0.05)	−0.11 (−0.23, 0.01)
Personal history of breast cancer
No	Reference	Reference	Reference
Yes	0.19 (− 0.27, 0.48)	0.14 (0.03, 0.25)	0.08 (−0.03, 0.19)
Personal history of any other cancer
No	Reference	Reference	Reference
Yes	0.39 (− 0.52, 1.02)	−0.03 (−0.25, 0.19)	−0.13 (−0.36, 0.09)
First-degree family history of breast cancer
No	Reference	Reference	Reference
Yes	0.17 (− 0.39, 0.31)	0.12 (0.02, 0.22)	0.10 (0.00, 0.21)
Ever had a cancer genetic test
No	Reference	Reference	Reference
Yes	0.66 (0.17, 1.15)	0.02 (−0.12, 0.16)	0.07 (−0.08, 0.22)
Total knowledge score	–	0.00 (−0.02, 0.02)	0.04 (0.02, 0.06)

^*Adjusted for all variables in the table. β represents the expected difference in means

Attitudes and self-efficacy. Attitudes toward genetic testing and perceived self-efficacy in using genetic information were generally favorable. Mean attitude scores (out of 5) were 4.2 (SD, 0.7) and 4.0 (SD, 0.6) among women with and without breast cancer, respectively. Corresponding mean self-efficacy scores were 3.9 (SD, 0.6) and 3.8 (SD, 0.7). Women with a personal history of breast cancer had somewhat more favorable attitudes toward genetic testing compared to those with no prior history of breast cancer (β: 0.14; 95% CI: 0.03, 0.25); similar associations were observed for family history of breast cancer (β: 0.12; 95% CI: 0.02, 0.22). Older age (β: –0.08 per 10 years; 95% CI: –0.14, –0.03) and never having been married (β: –0.16; 95% CI: –0.28, –0.05) were associated with less favorable attitudes toward genetic testing. Predictors of higher self-efficacy included educational attainment [β for women with ≥17 years of education vs. ≤12 years was 0.31 (95% CI: 0.15, 0.47)], first-degree family history of cancer (β: 0.10; 95% CI: 0.00, 0.21), and total knowledge score (β: 0.04; 95% CI: 0.02, 0.06) (Table 2).

Discussion

In this cohort of U.S. Black women, overall cancer genetics knowledge was relatively high. Our findings of high levels of knowledge are in line with other recent reports in this population [19, 33]. In a study of genetic knowledge in a medically underserved population (58% Black; 62% in “fair” or “poor” health), participants had a mean knowledge score of 3.5 (out of 5) (SD, 1.1). Black race, age, and educational attainment were significant predictors of knowledge, after adjusting for health literacy, gender, and marital status. That study was not specific to cancer genetics knowledge or any other specific disease [33]. In another study including 22 Black women with early-stage breast cancer, high levels of genetic knowledge were reported, with a mean score of 11.1 out of 16 (SD: 3.4); however, the questionnaire was not specific to cancer genetics [19]. Similar to our study participants, this was a highly educated population and education was positively correlated with genetic literacy. The observed association of age and education with genetic knowledge is also consistent with other reports in both general [33, 34] and cancer-specific research [28].

Despite relatively high levels of cancer genetic knowledge in our study, evaluation of individual-level knowledge questions revealed opportunities for targeted education in some specific areas. Specifically, there were notable gaps in knowledge related to understanding the inherited genetic etiology of cancer, limitations of genetic testing, and relevance of a variant of uncertain significance to cancer screening recommendations. In addition, older women, those with lower educational attainment and women who are not married or living as married (which may reflect more limited social support and/or economic instability) may benefit from more targeted education about genetic cancer testing. Finally, despite the role genetic testing currently plays in guiding cancer treatment, Black women who had breast cancer did not have higher knowledge scores than those without breast cancer and therefore may also benefit from targeted education.

Study participants report generally favorable attitudes toward cancer genetic testing and a high degree of self-efficacy. These findings are perhaps not surprising, as Black women (and men) have consistently reported favorable attitudes (perceived benefits) toward cancer genetic testing [35–37]. Among 658 Black men and women recruited from motor vehicle records in North Carolina for a study of intentions to pursue genetic testing for colorectal cancer, a majority reported high perceived benefits to genetic testing, with 78% agreeing or strongly agreeing that it is good to know about future disease risk and 79% agreeing or strongly agreeing that taking a genetic test would give them more control over their lives [16]. In that study, perceived benefits were strongly associated with intent to test. In a separate survey of 945 Black women with breast cancer, 27% of whom had undergone BRCA1/2 testing, attitudes toward BRCA1/2 testing were assessed in 8 items covering the domains of benefits (e.g., testing would help with personal or family cancer risk management), cost, and potential adverse effects (e.g., testing would lead to problems with family members or with job). As in our study, authors reported overall positive attitudes (28.4 among those who tested and 25.5 among those who did not test, out of 40 maximum points) [38]. In a cross-sectional analysis of the Health Information Trends Survey 5, Alkhatib et al. report favorable attitudes toward cancer genetic testing among Black individuals, with >80% reporting that a person’s genetic information is important or very important for preventing, detecting, or treating cancer [36]. In focus groups with Black breast cancer patients (n=13) and unaffected Black women with a family history of breast or ovarian cancer (n=8), Sheppard et al. reported generally favorable attitudes toward genetic testing [39]. Similarly, in interviews with 11 Black women with either a personal or family history of breast cancer, respondents perceived BRCA1/2 testing as beneficial to themselves and/or to relatives [20]. Fewer studies evaluated self-efficacy in genetic testing; in the study of a medically underserved population described above, participants had a moderate degree of self-efficacy (M= 3.2 on a 5-point scale, SD=1.1) [33]. Collectively, these findings suggest that personal attitudes toward cancer genetic testing are not likely major drivers of racial disparities in receipt of testing.

In the present study, predictors of favorable attitudes or higher self-efficacy included younger age, higher educational attainment, being married, and prior diagnosis of breast cancer. In a sample of 74 African American women with either a personal history of breast or ovarian cancer or a high risk of these cancers, attitudes were generally positive [22]. In that study, older age was associated with more favorable attitudes toward cancer genetic testing, in contrast to our study findings. In a prior study of predominantly White individuals, age, educational level, and a family history of cancer were associated with higher cancer genetic knowledge scores and higher knowledge scores were in turn associated with more favorable attitudes toward genetic testing [28]. In the present study, we observed that having had prior cancer genetic testing was associated with higher cancer genetic knowledge, but temporality is difficult to establish: greater knowledge could have led to uptake of genetic testing in this population.

Our study population, drawn from the BWHS cohort, is a highly educated population engaged in a long-term health research study, with the majority of participants having completed college. Further, nearly 40% of breast cancer survivors reported having had prior genetic testing for cancer; thus, findings of this study may not be generalizable to less educated or engaged populations. Relatively high overall knowledge scores could reflect a “ceiling effect” of this measure and limited our ability to detect differences between groups. Strengths of this study include the sample size, reflecting one of the largest studies of cancer genetics knowledge and attitudes among Black women to date, and the comprehensive assessment of knowledge, attitudes, and self-efficacy constructs using measures adapted from published literature.

For a number of individual and structural reasons, individuals from racially minoritized groups are less likely to undergo genetic testing than those from majority groups [10–13]. Among individual-level factors related to testing, knowledge and awareness increase the likelihood of pursuing genetic testing, including among racial minority groups [16]. Results of this study affirm prior reports of favorable attitudes toward cancer genetic testing among Black women and reveal some gaps in knowledge that could inform strategies to increase uptake of genetic testing in this high-risk population and help advance access to quality care and personalized medicine. Our findings of high levels of cancer genetics knowledge and favorable attitudes further suggest that addressing system-level barriers to genetic testing will be critical to improve cancer outcomes among Black women.

Author contributions

JRP and CW contributed to the study conception and design. Data collection was performed by KAB, JRP, and CW. Statistical analyses were performed by KAB with input from HJC. The first draft of the manuscript was written by KAB; all authors provided critical feedback on the draft and read and approved the final manuscript.

Funding

This work was supported by the National Institutes of Health (MD014312 and CA164974). Julie R. Palmer received support from the Karin Grunebaum Cancer Research Foundation.

Data availability

The data underlying this article cannot be shared publicly to protect the confidentiality of individuals who participated in the study. The data will be shared on reasonable request to the corresponding author.

Declarations

Conflicts of interests

The authors declare that they have no conflicts of interest.

Ethics approval and consent to participate

The BWHS study protocol was approved by the Boston University Medical Campus Institutional Review Board (IRB). All participants provided written informed consent for this study.