Background
Pragmatic trials, because they study widely used treatments in settings of routine practice, require intensive participation from clinicians who determine whether patients can be enrolled. Clinicians are often conflicted between their therapeutic obligation to patients and their willingness to enroll them in trials in which treatments are randomly determined and thus potentially suboptimal. Refusal to enroll eligible patients can hinder trial completion and damage generalizability. In order to help evaluate and mitigate clinician refusal, this qualitative study examined how clinicians reason about whether to randomize eligible patients.