BACKGROUND:Patients with osteoporosis can sustain fractures following falls or other minimal trauma. This risk of fracture can be reduced through appropriate diagnostic testing, pharmacologic therapy, and other readily measured standards of care. OBJECTIVES: Our aim was to develop a credible clinical performance assessment to measure physicians' quality of osteoporosis care, and determine reasonable performance standards for both competent and excellent care. DESIGN: This was a retrospective cohort study. PARTICIPANTS: Three hundred and eighty one general internists and subspecialists with time-limited board certification were included in the study. MAIN MEASURES: Performance rates on eight evidencebased measures were obtained from the American Board of Internal Medicine (ABIM) Osteoporosis Practice Improvement Module® (PIM), a web-based tool that uses medical chart reviews to help physicians assess and improve care. We applied a patented methodology, using an adaptation of the Angoff standard-setting method and the Dunn-Rankin method, with an expert panel skilled in osteoporosis care to form a composite and establish standards for both competent and excellent care. Physician and practice characteristics, including a practice infrastructure score based on the Physician Practice Connections Readiness Survey (PPC-RS), were used to examine the validity of the inferences made from the composite scores. KEY RESULTS: The mean composite score was 67.54 out of 100 maximum points with a reliability of 0.92. The standard for competent care was 46.87, and for excellent care it was 83.58. Both standards had high classification accuracies (0.95). Sixteen percent of physicians performed below the competent care standard, while 22 % met the excellent care standard. Specialists scored higher than generalists, and better practice infrastructure was associated with higher composite scores, providing some validity evidence. CONCLUSIONS: We developed a rigorous methodology for assessing physicians' osteoporosis care. Clinical performance feedback relative to absolute standards of care provides physicians with a meaningful approach to selfevaluation to improve patient care.