Bice-Boxerman Continuity of Care Primary Care Physician Measure (BB-COC-PC). At a patient-level, BB-COC is a measure that considers the dispersion of primary care visits across providers, such that patients with higher scores have most of their primary care visits to the same provider or a small number of providers while those lower scores see a larger number providers. Formally, an individual BB-COC score is calculated as follows: BB-COC=(∑_(i=1)^k n_i^2 -N)/(N(N-1)) (1) where k is the number of providers, n_i is the number of visits to provider i, and N is the total number of visits. (Note that it is necessary that the patient has at least two visits.) We will calculate the physician-level continuity measure for all patients as follows: BB-COC-PC=(∑_1^k 〖((BB-COC)(n_k ))〗)/(N*(n_k)) (2) Where BB-COC is the individual patient continuity score, n is number of total primary care visits for patient k during the study period, and N is the total number of patients seen by the physicians during the study period. This approach gives greater weight to patients with more visits.