• complex disease;
  • genetic biobank;
  • nonparticipation

Purpose: To identify demographic differences between patients who choose participation and patients who choose nonparticipation in genetic biobanks, and to explore reasons for nonparticipation.

Design: Prospective study of hospitalized cardiovascular patients approached to participate in a genetic biobank, 300 nonparticipants and 299 participants, in the southwestern US.

Methods: Reasons for nonparticipation were explored. Logistic regression was performed to determine if gender, race or ethnicity, or age predicted nonparticipation.

Findings: Race or ethnicity and age were significantly different between participants and nonparticipants, but gender was not. Blood-sample collection was the main reason for declining participation.

Conclusions: Minority and older adults were less likely to participate. Understanding reasons for nonparticipation in this group might aid in the development of methods used to obtain a diverse population in biobanks.