Introduction: To describe the rationale and design of an NIH funded randomized controlled trial: the Patient Activation after DXA Result Notification (PAADRN) study. The aim of this trial is to evaluate the effect that a direct mailing of Dual-Energy X-ray Absorptiometry (DXA) results from bone density testing centers to patients will have on patients' knowledge, treatment and self-efficacy. Methods: We will enroll approximately 7500 patients presenting for DXA at three study sites, the University of Iowa, the University of Alabama at Birmingham, and Kaiser Permanente of Atlanta, Georgia. We will randomize providers (and their respective patients) to either the intervention arm or usual care. Patients randomized to the intervention group will receive a letter with their DXA results and an educational brochure, while those randomized to usual care will receive their DXA results according to standard practice. The seven discrete outcomes are changes from baseline to 12-weeks and/or 52-weeks post-DXA in: (1) guideline concordant pharmacologic and non-pharmacologic therapy; (2) knowledge of DXA results; (3) osteoporosis-specific knowledge; (4) general health-related quality of life; (5) satisfaction with bone-related health care, (6) patient activation; and, (7) osteoporosis-specific self-efficacy. Conclusion: This trial will offer evidence of the impact of a novel approach-direct-to-patient mailing of test results-to improve patient activation in their bone health care. The results will inform clinical practice for the communication of DXA and other test results. © 2012 Elsevier Inc.