Another challenge to the conventional (American) wisdom on privatization: U.S. hospitals owned by investors with the aim of making money are less cost-efficient than nonprofits, Canadian researchers said. And experts who wrote a commentary on the study said converting all investor-owned hospitals to nonprofit status could have saved $6 billion in 2001. The report, published in Monday's issue of the Canadian Medical Association Journal, adds fuel to the debate over whether health care should follow a business model. Dr. P.J. Devereaux and colleagues at McMaster University in Hamilton, Ontario, reviewed medical studies on hospital care in the United States, covering 350,000 patients and hundreds of hospitals. Devereaux, a cardiologist, said he had to study U.S. hospitals because "the U.S. is really the only country which has any large degree of investor-owned, for-profit health facilities," he said in a telephone interview.