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In page Health system:

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Most countries' systems feature a mix of all five models. One study[2] based on data from the OECD concluded that all types of health care finance "are compatible with" an efficient health system. The study also found no relationship between financing and cost control.[citation needed] Another study examining single payer and multi payer systems in OECD countries found that single payer systems have significantly less hospital beds per 100,000 people than in multi payer systems.[3]