Article Title

Feasibility of Establishing a Cohort in the Setting of U.S. Health Care Systems

Publication Date



feasibility study, cancer


Background/Aims: Epidemiologic cohorts have contributed substantially to our understanding of potential risk factors and biological markers for cancer and other chronic diseases. Integrated health care systems offer a promising setting to establish a new large-scale prospective biospecimen-based cohort for research on disease etiology and outcomes. Health care systems with electronic medical records provide some unique advantages for establishing the next generation of cohort studies. Our objective in this Kaiser Permanente Colorado (KPCO) pilot study was to assess the feasibility of leveraging existing health care system infrastructure to establish a prospective cohort.

Methods: In 2014, a total of 1,350 eligible KPCO members (aged 40–74 years, cancer-free, KPCO member for at least 12 months) were invited to participate, 850 via email and 500 via mail. Participants were asked to provide a blood sample and to complete a self-report risk factor survey. An interactive voice response system was used for participant reminders.

Results: Of those randomized to receive an email invitation to participate, 630 (74%) had a valid email address; 98% (n = 490) in the mail arm had a valid mailing address for a total of 1,120 contactable members. Overall, 115 individuals consented to participate, with greater recruitment success in the email arm (12%) than in the mail arm (8%). Of those who consented, 86 (75%) provided a blood sample and 94 (82%) completed and returned the survey by mail. In both arms, more females than males consented, with the highest consent rate among 60–69-year-olds and the lowest among 40–49-year-olds. The majority of participants in both arms were non-Hispanic white. Compared to the mail arm, there was a greater consent rate among women (68% vs. 57%), African-Americans (5% vs. 3%) and Hispanics (22% vs. 17%) in the email arm. There was a lower consent rate in the email arm among members over 70 years old (9% vs. 20%).

Conclusion: The success of this study demonstrates the feasibility of implementing a biospecimen-based cohort in a health care system setting. The study also served to highlight potential problems as well as solutions to these issues.




June 24th, 2016


August 12th, 2016