The ability of PHI to reduce demand pressures on the public system has nonetheless proven to be constrained. Increases in the population covered by PHI in Australia and Ireland have not resulted in unambiguous signs of decline in the level of waiting (Colombo and Tapay, 2003 and 2004b). PHI membership has not only shifted demand across public and private hospitals but has also increased overall demand, thereby limiting the impact on waiting times. In some countries, incentives created by higher payment levels in PHI markets have also encouraged providers to maintain long queues in the public system or refer patients to owned private facilities in order.
