Characteristic of study subjects by examination status by ethnicity, age group, and sex, n (%)
| Population in study areas | People selected | People examined | Not available | Refused | Unable | |
| Ethnicity | ||||||
| Tibetan | 854 827 (78.3) | 4323 (86.5)* | 4127 (95.5) | 101 (2.34) | 46 (1.06) | 49 (1.13) |
| Han | 199 157 (18.2) | 523 (10.5)* | 495 (94.7) | 8 (1.53) | 5 (0.96) | 15 (2.87) |
| Other | 37 888 (3.47) | 154 (3.08) | 142 (92.2) | 0 (0.00) | 2 (1.30) | 10 (6.49)† |
| Total | 1 091 872 (100.0) | 5000 (100.0) | 4764 (95.3) | 109 (2.18) | 53 (1.06) | 74 (1.48) |