1. Department of Internal Medicine, The Catholic University of Korea, Korea.
2. Hong Ik Hospital, Korea.
3. Noh Medical Clinic, Korea.
4. Suh Medical Clinic, Korea.
5. Youn Medical Clinic, Korea.
6. Lee Kwan Woo Medical Clinic, Korea.
7. Lee Medical Clinic, Korea.
8. Hana Medical Clinic, Korea.
9. Konyang University Hospital, Korea.