| Characteristics | n | (%) |
|---|---|---|
| Gender (n=1,638) | ||
| Male | 776 | 47.37 |
| Female | 862 | 52.63 |
| Ethnic group (n=1,638) | ||
| The Kinh | 1,546 | 94.38 |
| Other | 92 | 5.62 |
| Age, | 28 (18–58) | |
| Age group (years) (n=1,638) | ||
| 18–24 | 769 | 46.95 |
| 25–35 | 536 | 32.72 |
| 36–44 | 218 | 13.31 |
| 45–60 | 115 | 7.02 |
| Weight (kg) (n=1,638) | ||
| 42–50 | 382 | 23.32 |
| 51–60 | 682 | 41.64 |
| >60 | 574 | 35.04 |
| Occupation (n=1,638) | ||
| Student | 511 | 31.20 |
| Officer | 331 | 20.21 |
| Police – Military | 75 | 4.58 |
| Worker – Farmer | 386 | 23.56 |
| Self-employed – others | 335 | 20.45 |
| Blood group (n=1,610) | ||
| A | 320 | 19.88 |
| B | 486 | 30.19 |
| O | 715 | 44.41 |
| AB | 89 | 5.53 |