Enrollment of racial and ethnic minorities in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial

J Natl Med Assoc. 2008 Mar;100(3):291-8. doi: 10.1016/s0027-9684(15)31241-4.


Background: Minority populations in the United States, especially blacks and Hispanics, are generally underrepresented among participants in clinical trials. Here, we report the experience of enrolling ethnic minorities in a large cancer screening trial.

Methods: The Prostate, Colorectal, Lung and Ovarian (PLCO) Cancer Screening Trial is a multicenter randomized trial designed to evaluate the effectiveness of screening for the PLCO cancers. Subjects were recruited at 10 U.S. centers between 1993 and 2001. One screening center had a major special recruitment effort for blacks and another center had a major special recruitment effort for Hispanics.

Results: Among almost 155,000 subjects enrolled in PLCO, minority enrollment was as follows: black (5.0%), Hispanic (1.8%) and Asian (3.6%). This compares to an age-eligible population in the combined catchment areas of the PLCO centers that was 14.0% black, 2.9% Hispanic and 5.4% Asian, and an age-eligible population across the U.S. that was 9.5% black, 6.5% Hispanic and 3.0% Asian. About half (45%) of Hispanics were recruited at the center with the special Hispanic recruitment effort. Seventy percent of blacks were recruited at two centers; the one with the major special recruitment effort and a center in Detroit whose catchment area was 20% black among age-eligibles. Blacks, Hispanics and (non-Hispanic) whites were all more highly educated, less likely to currently smoke and more likely to get regular exercise than their counterparts in the general population.

Conclusion: Significant efforts were made to recruit racial/ ethnic minorities into PLCO, and these efforts resulted in enrollment levels that were comparable to those seen in many recent cancer screening or prevention trials. Blacks and Hispanics were nonetheless underrepresented in PLCO compared to their levels among age-eligibles in the overall U.S. population or in the aggregate PLCO catchment areas.

Publication types

  • Clinical Trial
  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial

MeSH terms

  • African Americans / statistics & numerical data
  • Aged
  • Asian Americans / statistics & numerical data
  • Attitude to Health
  • Colorectal Neoplasms / diagnosis*
  • Colorectal Neoplasms / epidemiology
  • Ethnicity / statistics & numerical data*
  • Female
  • Hispanic or Latino / statistics & numerical data
  • Humans
  • Lung Neoplasms / diagnosis*
  • Lung Neoplasms / epidemiology
  • Male
  • Mass Screening*
  • Middle Aged
  • Minority Health
  • Ovarian Neoplasms / diagnosis*
  • Ovarian Neoplasms / epidemiology
  • Patient Acceptance of Health Care
  • Patient Satisfaction
  • Patient Selection*
  • Prostatic Neoplasms / diagnosis*
  • Prostatic Neoplasms / epidemiology
  • United States / epidemiology
  • Whites / statistics & numerical data