Research has shown associations between patient complaints and patient outcomes. This study evaluated the impact of an evidence-based intervention to reduce patient complaints in one orthopedic practice. The Patient Advocacy Reporting System (PARS) includes a peer messenger component for the small proportion of clinicians whose practices are associated with a disproportionate share of patient complaints. Of the 42 physicians and physician assistants who were identified by PARS as at-risk for patient complaints, 90% improved following peer-delivered feedback. In addition, malpractice claims against those clinicians decreased by 87%.