U.S. doctors are turning away an increasing number of patients, including those with private insurance, according to a study in the Archives of Internal Medicine. Physicians were willing to accept about 88 percent of patients who had private insurance in 2008, down from 93 percent in 2005, the study released today found. Patients in Medicare, the U.S. health insurance program for the elderly and disabled, also had a harder time finding a doctor. About 93 percent were accepted by physicians in 2008, down from 96 percent in 2005. The drop in doctors willing to take private insurance was caused by low payments for services as well as administrative difficulties, said Dr. Tara Bishop, an assistant professor of public health at Weill Cornell Medical College in New York.