Does Your Doctor Matter? Doctor Quality and Patient Outcomes

We estimate doctor value-added and provide evidence on the distribution of physician quality in an entire country, combining rich population-wide register data with random assignment of patients to general practitioners (GPs). We show that there is substantial variation in the quality of physicians, as measured by patients’ post-assignment mortality, in the primary care sector. Specifically, a one standard deviation increase in doctor quality is associated with a 12.2percentage point decline in a patient’s two-year mortality risk. While we find evidence of observable doctor characteristics and practice styles influencing a GP’s value-added, a standard decomposition exercise reveals that most of the quality variation is driven by unobserved differences across doctors. Finally, we show that patients are unable to identify who the highquality doctors are, and that patient-generated GP ratings are uncorrelated with GP value-added. Using a lower bound of the predicted value of an additional life year in Norway ($35,000), our results demonstrate that replacing the worst performing GPs (bottom 5 percent of the VA distribution) with GPs of average quality generates a social benefit of $27,417 per patient, $9.05 million per GP, or $934 million in total. At the same time, our results show that higher-quality GPs are associated with a lower per-patient cost.