The number of dually accredited programs increased from 11% of all AOA approved residencies in 2006 to 14% in 2008, and then to 22% in 2010. In 2000, the AOA adopted a provision making it possible for a DO resident in any MD program to apply for osteopathic approval of their training. The topic of dual-accreditation is controversial. Opponents claim that by merging DO students into the "MD world," the unique quality of osteopathic philosophy will be lost. Supporters claim the programs are popular because of the higher prestige and higher resident reimbursement salaries associated with MD programs.