Physician-induced demand by Irish GPs.

Approximately one-third of the Irish population receive all medical care services free. GPs (general practitioners) treat both public and private patients, and are remunerated on a fee-for-service basis by the state for public patients, and by the patient, at a higher rate, for private patients. In 1981, the first author conducted a national survey of Irish medical care utilization, asking whether patients' most recent GP visits resulted in a return visit being arranged. This measure of self-referral by GPs is significantly and strongly associated with the ratio of GPs to population, and negatively with the ratio to population of persons eligible for free services, and with area per capita income. All three results are as hypothesized from a theoretical model, and point to significant self-interested physician-induced demand by Irish GPs.