Do High Quality Physicians Have High Quality Patients?

What makes some physicians perform better than others? This paper examines two different channels through which primary care doctors’ patient management styles can affect health outcomes: by prescribing the appropriate clinical therapy and by inspiring better patient health management, as reflected in the patient’s adherence to that therapy. Using data on the population of statin-users in Denmark that matches patients to primary care physicians, we show that the impact of a physician’s clinical quality on patient health outcomes is largely explained by the composition of patients in the physician’s practice. In contrast, the physician’s skill in facilitating adherence to prescription drugs maintains large and positive effects on patient outcomes even after controlling for patient composition. We also show that the health effects of adherence to commonly prescribed anti-cholesterol drugs are large and significant.