1. Department of Family Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Division of Community Medicine, Taipei Municipal Yang-Ming Hospital, Taipei, Taiwan; Department of Family Medicine, Taipei Veterans General Hospital, No 201, Shih-Pai Road Sec 2, Taipei, Taiwan
2. Department of Family Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Family Medicine, Taipei Veterans General Hospital, No 201, Shih-Pai Road Sec 2, Taipei, Taiwan
3. Department of Family Medicine, Taipei Veterans General Hospital, No 201, Shih-Pai Road Sec 2, Taipei, Taiwan
4. Department of Family Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Family Medicine, Taipei Veterans General Hospital, No 201, Shih-Pai Road Sec 2, Taipei, Taiwan National Yang-Ming University School of Medicine, Taipei, Taiwan