Background: Although clinical pathways have the promise to improve the quality of care, they have had limited success changing practice or standardizing care. Moffitt Cancer Center (MCC) has > 40 pathways incorporating interdisciplinary care strategies linked to evidence and decision support tools. Methods: To improve compliance with pathways we used an innovative measure to quantify quality of care, CPV vignettes. CPV vignettes are validated, simulated clinical scenarios constructed so that adherence to pathways is clear-cut. Providers care for identical cases so there is no need for case mix adjustment. After completing each case, providers are given personalized feedback. Twelve breast cancer (ca) vignettes were developed by MCC breast medical oncologists and surgeons and QURE, a healthcare measurement company. The cases were developed using MCC pathways, other evidence and core issues such as diagnostic work-up. The vignettes were randomized at the department level and given to all MCC providers who care for breast ca patients. A total of 18 providers took 34 CPVs: 7 medical oncologists, 6 advanced practitioners and 5 surgeons. QURE-trained physician abstractors blinded to the CPV-taker’s identity scored each vignette and provided confidential feedback. Results: Total scores for providers averaged 55.4%, s.d. 12.5%, a typical score for a CPV baseline study. Adherence to pathways varied by area with the highest concordance for radiation and hormonal therapy and the lowest for management of axillary lymph nodes (see Table). Conclusions: Adherence to pathways varied among providers and by clinical domain. Ongoing efforts will evaluate the impact of serial CPV measurement on pathway adherence. Simulations simplified the task of determining pathway adherence making pathway compliance at the physician level a reasonable expectation and standardization at the group level scientifically rigorous and feasible.