Competition, gatekeeping, and health care access.

We study gatekeeping physicians' referrals of patients to specialty care. We derive theoretical results when competition in the physician market intensifies. First, due to competitive pressure, physicians refer patients to specialty care more often. Second, physicians earn more by treating patients themselves, so refer patients to specialty care less often. We assess empirically the overall effect of competition with data from a 2008-2009 Norwegian survey, National Health Insurance Administration, and Statistics Norway. From the data we construct three measures of competition: the number of open primary physician practices with and without population adjustment, and the Herfindahl-Hirschman index. The empirical results suggest that competition has negligible or small positive effects on referrals overall. Our results do not support the policy claim that increasing the number of primary care physicians reduces secondary care.