1. Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan
2. Department of Health Management, I-Shou University, Kaohsiung, Taiwan
3. Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan 2National Yang-Ming University, School of Medicine, Taipei, Taiwan
4. Community Medicine Research Center and Institute of Public Health, National Yang-Ming University, Taipei, Taiwan