Purchase Using the Pay Card (Human Subjects) Learn about how to make a purchase using the Pay Card for Human Subjects at Columbia University. Expand all Collapse all 1 Resources for Using the Pay Card Overview For an overview of the PayCard, please refer to the Prepaid Card Community Brochure. FAQs For frequently asked questions — Refer to the Anonymous PayCard FAQ Refer to the Registered PayCard FAQ Still have questions? Visit our Service Center.