Table S4. Demographics for participants according to PDI.
| Variables | n (%) | χ2 | P | |||
| Quartile 1 | Quartile 2 | Quartile 3 | Quartile 4 | |||
| PDI, overall plant-based diet index; BMI, body mass index. | ||||||
| Gender | ||||||
| Male | 1,898 (50.00) | 1,966 (45.50) | 1,903 (45.59) | 1,216 (42.03) | 43.502 | <0.001 |
| Female | 1,898 (50.00) | 2,355 (54.50) | 2,271 (54.41) | 1,677 (57.97) | ||
| Age at baseline (year) | ||||||
| 40−49 | 1,488 (39.20) | 1,764 (40.82) | 1,758 (42.12) | 1,281 (44.28) | 23.043 | <0.001 |
| 50−59 | 1,626 (42.83) | 1,812 (41.93) | 1,655 (39.65) | 1,141 (39.44) | ||
| 60−69 | 682 (17.97) | 745 (17.24) | 761 (18.23) | 471 (16.28) | ||
| Marital status | ||||||
| Married | 3,501 (92.23) | 4,052 (93.77) | 3,899 (93.41) | 2,737 (94.61) | 16.332 | <0.001 |
| Unmarried/divorced/widowed | 295 (7.77) | 269 (6.23) | 275 (6.59) | 156 (5.39) | ||
| Educational status | ||||||
| No education | 446 (11.75) | 581 (13.45) | 624 (14.95) | 570 (19.70) | 94.141 | <0.001 |
| Elementary school | 1,439 (37.91) | 1,563 (36.17) | 1,506 (36.08) | 937 (32.39) | ||
| Middle school and above | 1,911 (50.34) | 2,177 (50.38) | 2,044 (48.97) | 1,386 (47.91) | ||
| No. of family members | ||||||
| 1−2 | 885 (23.31) | 955 (22.10) | 925 (22.16) | 574 (19.84) | 15.592 | 0.211 |
| 3 | 698 (18.39) | 803 (18.58) | 793 (19.00) | 584 (20.19) | ||
| 4 | 1,253 (33.01) | 1,471 (34.04) | 1,372 (32.87) | 993 (34.32) | ||
| 5 | 638 (16.81) | 705 (16.32) | 705 (16.89) | 486 (16.80) | ||
| ≥6 | 322 (8.48) | 387 (8.96) | 379 (9.08) | 256 (8.85) | ||
| Annual income (CNY/person) | ||||||
| ≤5,000 | 1,366 (35.99) | 1,376 (31.84) | 1,336 (32.01) | 848 (29.31) | 35.738 | <0.001 |
| >5,000 | 2,430 (64.01) | 2,945 (68.16) | 2,838 (67.99) | 2,045 (70.69) | ||
| BMI (kg/m2) | ||||||
| <18.5 | 161 (4.24) | 134 (3.10) | 116 (2.78) | 112 (3.87) | 17.982 | 0.035 |
| 18.5−23.9 | 2,136 (56.27) | 2,452 (56.75) | 2,359 (56.52) | 1,616 (55.86) | ||
| 24.0−27.9 | 1,197 (31.53) | 1,369 (31.68) | 1,349 (32.32) | 941 (32.53) | ||
| ≥28.0 | 302 (7.96) | 366 (8.47) | 350 (8.39) | 224 (7.74) | ||
| Smoking status | ||||||
| No | 2,556 (67.33) | 3,037 (70.28) | 3,082 (73.84) | 2,298 (79.43) | 133.830 | <0.001 |
| Yes | 1,240 (32.67) | 1,284 (29.72) | 1,092 (26.16) | 595 (20.57) | ||
| History of digestive diseases | ||||||
| No | 3,313 (87.28) | 3,851 (89.12) | 3,722 (89.17) | 2,514 (86.90) | 15.152 | 0.002 |
| Yes | 483 (12.72) | 470 (10.88) | 452 (10.83) | 379 (13.10) | ||
| Family history of cancer | ||||||
| No | 2,700 (71.13) | 2,973 (68.80) | 2,948 (70.63) | 2,084 (72.04) | 10.013 | 0.018 |
| Yes | 1,096 (28.87) | 1,348 (31.20) | 1,226 (29.37) | 809 (27.96) | ||