Improving Minority Participation in Prevention Trials

Improving Minority Participation in Prevention Trials

CHICAGO—Advances in cancer screening, prevention, and treatment have led to decreased cancer incidence and mortality. However, the benefits of new early detection measures and treatment options are not shared equally among ethnic minorities and the medically underserved, and disparities in cancer morbidity and mortality remain.

For example, blacks have the highest overall incidence of cancer of any racial or ethnic group in the United States and are 33% more likely than whites to die of cancer.[1]

Black women have the highest rates of colorectal and lung cancers and have the highest mortality rates for breast, colorectal, and lung cancer. Black men have the highest incidence of and mortality from prostate, colorectal, and lung cancers.[1] Blacks have low rates of cancer screening and low rates of participation in cancer clinical trials.

The IOM Report

The disproportionate burden of cancer led to the Congressional request that the Institute of Medicine (IOM) review the National Institutes of Health’s research and programs for ethnic minorities and the medically underserved.[2] The IOM’s report has drawn attention to low rates of minority participation in cancer screening and prevention studies.

Clinical trials play a crucial role in cancer research. Assuring that new treatment and prevention approaches are effective and safe for the general population requires large-scale, randomized, double-blind clinical trials. However, recruitment is challenging, with less than 5% of eligible cancer patients being enrolled in clinical treatment trials.[3]

To ensure that research findings can be generalized to and are applicable to diverse populations, clinical trials should include adequate representation from minority populations.

Despite efforts to increase minority enrollment into cancer prevention trials, however, minority participation rates remain low. For example, in the ongoing Prostate Cancer Prevention Trial (PCPT) and Breast Cancer Prevention Trial (BCPT), minority enrollment rates did not reach 5%.[2,4]

In addition to increasing minority participation in prevention trials, decreasing cancer incidence and improving cancer survival requires successful implementation of new technologies for cancer screening and early detection, some of which have only recently become available to the public. (One such technology, genetic screening for mutations in cancer susceptibility genes, will be discussed in an upcoming article in this series.)

Low minority participation rates in cancer screening and prevention trials suggest that barriers to participation have not been adequately addressed. Targeted research and interventions are necessary for decreasing cancer rates in ethnic minorities and the medically underserved.

This paper will address the work by Marvella Ford, PhD, of the Henry Ford Health Care System, Detroit, on recruitment of blacks into cancer chemopre-vention trials, as presented at the Robert H. Lurie Comprehensive Cancer Center’s Health Policy Symposium—Cancer: Reaching Medically Underserved Populations.

Minority Recruitment Goals

Successful cancer prevention trials require recruitment and retention of large numbers of healthy asymptomatic participants. In addition, lengthy trial periods of 10 years or more are often necessary to detect any differences in tumor development between the intervention and placebo arms.

Unlike treatment trials where participants receive high-quality standard care and/or the experimental treatment, all participants in prevention trials are healthy and therefore may not receive any supplemental care. In addition, those who receive the intervention may experience adverse effects they would not experience if not in the trial, and those in the placebo arm may not experience any beneficial effects.

Ongoing prevention trials have not met target minority recruitment goals. For example, although black men over age 55 make up 8.2% of the US male population over age 55, of the 18,882 men randomized into the PCPT, 92% are white and only 4% are black.[4,5]

Disparities in minority recruitment in the BCPT are even more pronounced. More than 95% of the 13,266 participants are white, and only 2.1% are black, an accrual rate that is not representative of the disease burden in this population.


In another NCI-sponsored prevention trial, the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO), 89% of participants were white, 4.4% black, 1.4% Hispanic, 4.3% Asian American, and less than 0.5% other.[2]

To achieve appropriate representation of minorities in prevention trials, recruitment efforts must address barriers to minority enrollment. Barriers to minority participation in clinical trials include historical, sociocultural, economic, and individual factors.[6]

Blacks’ perceptions of clinical research have been influenced by the Tuskegee Syphilis Study that began in the 1930s and was designed to document the natural course of syphilis.

Although penicillin became standard treatment for syphilis in the 1940s, researchers did not provide information about or access to antibiotics. The men were left untreated into the early 1970s, when the study was disclosed and subsequently shut down.[7]

Sociocultural, Economic Barriers

Sociocultural barriers include lack of access to information about clinical trials, mistrust of the health care system, fear of being used as a guinea pig, cultural beliefs about specific diseases or illness in general, fatalism, or embarrassment.[8,9]

The largest economic barrier to participation of minority and low-income persons is lack of health insurance. In most cases, access to the health care system is a prerequisite for participation in clinical trials.

Other economic barriers include lack of transportation, the need for child care, and lost wages because of missed work. Individual barriers may include beliefs about personal invulnerability to disease.

The AAMEN Project

The African American Men (AAMEN) project began in 1996 as a collaboration between the Centers for Disease Control, the National Cancer Institute, and the Henry Ford Health Care System.[10] The project is designed to supplement the PLCO trial by determining the effectiveness of strategies to overcome participation barriers and increase the enrollment of black men in prostate cancer prevention trials.

The PLCO trial, which began in 1993, aims to determine if screening for and early detection of prostate, lung, colorec-tal, and ovarian cancer among healthy, asymptomatic adults aged 55 to 74 decreases mortality.

It is essential to include black men in such trials, since they have the highest incidence of prostate cancer as well as the highest mortality rate from this cancer.[1] Black men also have the lowest rates of participation in prostate cancer screening, such as digital rectal exams and prostate-specific antigen (PSA) blood tests.

The AAMEN project builds on previous focus group studies indicating that black men of low to middle socioeconomic status with greater knowledge about prostate cancer and screening for the disease are more willing to participate in prostate cancer clinical trials.[11]

The project uses commercial and public mailing lists to identify the names and addresses of black men aged 55 to 74 who live in the Detroit metropolitan area, and randomizes potential participants to one of three enhanced recruitment strategies.

Men in the first intervention are sent a packet of recruitment materials containing the photograph and signature of a black sports celebrity, a Detroit community leader, and a Detroit businessman approximately the same age as the men targeted by the AAMEN program.

The second intervention strategy includes telephone calls by trained black men to determine eligibility to participate in the PLCO trial. The third intervention employs recruitment sessions at local black churches.

Each of these interventions aims to overcome the recruitment barriers of mistrust and lack of awareness by disseminating information about the trial through individuals and institutions that the targeted population might trust. At this time, no preliminary data are available on the recruitment rates of the AAMEN project.

LSUMC-S Effort

Another intervention targeting blacks has already yielded promising results. Holcombe et al report success in recruiting black men into cancer prevention trials by identifying and addressing barriers to participation.[12]

Researchers at Louisiana State University Medical Center-Shreveport (LSUMC-S) have achieved recruitment of blacks above the nationwide average through a variety of techniques:

  • Using community-based recruitment approaches.
  • Working through Louisiana’s Charity Hospital System to avoid cost concerns.
  • Providing alternatives to written information.
  • Addressing suspicion and cultural concerns about clinical research in peer education groups.

As a result of these concerted efforts, 11% of patients enrolled in the PCPT through LSUMC-S are black, compared with 4% overall.


Persistent disparities in cancer incidence and mortality between whites and ethnic minorities in the United States suggest a need for targeted efforts to increase cancer screening and prevention measures among ethnic minorities and the medically underserved.

Since current clinical trial recruitment strategies are not reaching the diverse populations, cancer clinicians and other researchers may need to look at the recruitment strategies of studies in other areas of medicine that have successfully recruited large numbers of minorities.

For example, researchers exploring the effect of dietary patterns on blood pressure among adults with mild hypertension in the DASH trial used targeted mailings, mass mailings, community and worksite screening, and mass media advertising to recruit ethnic minorities. As a result of these efforts, two thirds of participants are minorities, and 60% are black.[13]

In another example of successful recruitment, the African American Antiplatelet Stroke Prevention Study (AAASPS), blacks were recruited by developing a community network involving community members, black churches and community organizations, and mass media advertising to spread information about the study.[14]


1. American Cancer Society: Cancer Facts and Figures 2000. Atlanta, American Cancer Society, 2000.

2. Haynes MA, Smedley BD (eds): The Unequal Burden of Cancer: An Assessment of NIH Research and Programs for Ethnic Minorities and the Medically Underserved. Washington, DC, National Academy Press, 1999.

3. Benson AB 3d, Pregler JP, Bean JA, et al: Oncologists’ reluctance to accrue patients onto clinical trials: An Illinois Cancer Center study. J Clin Oncol 9:2067-2075, 1991.

4. Coltman CA Jr, Thompson IM Jr, Feigl P, et al: Prostate Cancer Prevention Trial (PCPT) update. Eur Urol 35:544-547, 1999.

5. U.S. Census Bureau Population Division: Current Population Survey: Population by Age, Race and Hispanic Origin, and Sex. March 1999.

6. Swanson GM, Ward AJ: Recruiting minorities into clinical trials: Toward a participant-friendly system. J Natl Cancer Inst 87:1747-1759, 1995.

7. Caplan A, Edgar H, King P, et al: Twenty years later: The legacy of the Tuskegee Syphilis Study. Hastings Center Report 22(6):29-38, 1992.

8. Harris Y, Gorelick P, Samuels P, et al: Why African Americans may not be participating in clinical trials. J Natl Med Assoc 88:630-634, 1996.

9. Roberson NL: Clinical trial participation: Viewpoints from racial/ethnic groups. Cancer 74:2687-2691, 1994.

10. Ford ME, Havstad S: Recruiting black men to a clinical trial to evaluate prostate cancer screening—Detroit, Michigan, 1998. MMWR 47:694-696, 1998.

11. Robinson SB, Ashley M, Haynes MA, et al: Attitudes of African Americans regarding screening for prostate cancer. J Natl Med Assoc 88:241-246, 1996.

12. Holcombe RF, Jacobson J, Li A, et al: Inclusion of black Americans in oncology clinical trials: The Louisiana State University Medical Center experience. Am J Clin Oncol 22:18-21, 1998.

13. Vollmer WM, Svetkey LP, Appel LJ, et al: Recruitment and retention of minority participants in the DASH controlled feeding trial. Ethnicity and Disease 8:198-208, 1998.

14. Gorelick PB, Richardson D, Hudson E, et al: Establishing a community network for recruitment of African Americans into a clinical trial: The African American Antiplatelet Stroke Prevention Study (AAASPS) experience. J Natl Med Asso 88(11):701-704, 1996.

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