2.
Demographic baseline data of chronic gastritis patient population
| Characteristics | Case No. | % |
| Age (year) | ||
| ≤40 | 473 | 6.48 |
| 41–50 | 4,293 | 58.79 |
| 51–60 | 2,281 | 31.24 |
| >60 | 255 | 3.49 |
| Gender | ||
| Male | 5,008 | 68.58 |
| Female | 2,294 | 31.42 |
| Education | ||
| College and above | 824 | 11.28 |
| High school | 2,630 | 36.02 |
| Middle school | 3,356 | 45.96 |
| Primary school | 492 | 6.74 |
| Occupation | ||
| Worker | 5,246 | 71.84 |
| Peasant | 102 | 1.40 |
| Officer | 968 | 13.26 |
| Service | 255 | 3.49 |
| Retired | 629 | 8.61 |
| Others | 102 | 1.40 |
| Labor intensity | ||
| Light | 3,747 | 51.31 |
| Moderate | 2,553 | 34.96 |
| Heavy | 1,002 | 13.72 |
| Income (¥) | ||
| ≤2,000 | 1,597 | 21.87 |
| 2,001–3,000 | 5,229 | 71.61 |
| 3,001–4,000 | 1,751 | 23.98 |
| >4,000 | 1,425 | 19.52 |