Calcium and vitamin D intake and exercise are suboptimal among older adults. Following bone densitometry, a letter communicating individualized fracture risk accompanied by an educational brochure improved participants' lifestyle-but no more than existing communication strategies-over 52 weeks. Simple communication strategies are insufficient for achieving optimal levels of bone health behaviors. PURPOSE: The Patient Activation After DXA Result Notification (PAADRN) study was designed to evaluate whether a letter with individualized fracture risk and an educational brochure mailed to patients soon after their DXA might improve bone health behaviors (daily calcium intake, vitamin D supplementation, and weekly exercise sessions) compared to slower, less individualized communication characterizing usual care. METHODS: Participants ≥ 50 years were recruited, at three sites, following their DXA and randomized with 1:1 allocation to intervention and control (usual care only) groups. Data were collected at enrollment interview and by phone survey at 12 and 52 weeks thereafter. Intention-to-treat analyses were conducted on 7749 of the 20,397 eligible participants who enrolled. Changes in bone health behaviors were compared within and between study groups. Average treatment effects and heterogeneity of treatment effects were estimated with multivariable linear and logistic regression models. RESULTS: In unadjusted analyses, calcium intake, vitamin D supplementation, and weekly exercise sessions increased significantly over 52 weeks within both the intervention and control groups (all p < 0.001). In unadjusted analyses and multivariable models, increases in each behavior did not significantly differ between the intervention and control groups. Intervention group participants with a > 20% 10-year fracture risk at enrollment did, however, have a significantly greater increase in calcium intake compared to other study participants (p = 0.031). CONCLUSIONS: Bone health behaviors improved, on average, over 52 weeks among all participants following a DXA. Receipt of the PAADRN letter and educational brochure did not directly improve bone health behaviors compared to usual care. TRIAL REGISTRATION: The Patient Activation after DXA Result Notification (PAADRN) Study is registered at ClinicalTrials.Gov: NCT01507662, https://clinicaltrials.gov/ct2/show/NCT01507662.