Abstract Background To improve blood transfusion practices, we applied user-centered design (UCD) to evaluate potential changes to blood transfusion orders. Objectives The aim of the study is to build effective transfusion orders with different designs to improve guideline adherence. Methods We developed three different versions of transfusion orders that varied how information was presented to clinicians ordering blood transfusions. We engaged 14 clinicians (residents, advanced practice providers [APPs], and attending physicians) from different specialties. We used the think aloud technique and rapid qualitative analysis to generate themes to incorporate into our modified orders. Results Most end-users who participated in the semi-structured interviews preferred the interruptive alert design plus behavioral nudges (n = 8/14, 57%). The predominant rationale was that the in-line alert was not visually effective in capturing the end-user's attention, while the interruptive alert forced a brief stop in the workflow to consider the guidelines. All users supported the general improvements, though for different reasons, and as a result, the general improvements remained in the designs for the forthcoming trial. Conclusion The user experience uncovered through the think aloud approach produced a clear and rich understanding of potentially confounding factors in the initial design of different intervention versions. Input from end-users guided the creation of all three designs so each was addressing human factors with parity, which ensured that the results of our study reflected differences in interruptive properties of the alerts and not differences in design.