Table 1.
Comparison of major study variables between case patients and control subjects in the Molecular Epidemiology of Colorectal Cancer study in Israel*
| Variable | Unpaired |
Paired |
||||
| Case patients (n = 2648) | Control subjects (n = 2566) | P† | Case patients (n = 2566) | Control subjects (n = 2566) | P† | |
| No. (%) | No. (%) | No. (%) | No. (%) | |||
| Sex | .99 | 1.00 | ||||
| Men | 1342 (50.7) | 1301 (50.7) | 1301 (50.7) | 1301 (50.7) | ||
| Women | 1306 (49.3) | 1265 (49.3) | 1265 (49.3) | 1265 (49.3) | ||
| Age, mean, y | 69.9 | 70.6 | .06 | 69.8 | 70.6 | .03 |
| Ethnicity | .39 | .30 | ||||
| Non-Jews | 348 (13.1) | 317 (12.4) | 342 (13.3) | 317 (12.4) | ||
| Jews | 2300 (86.9) | 2249 (87.6) | 2224 (86.7) | 2249 (87.6) | ||
| Jewish ethnicity | <.001 | <.001 | ||||
| Ashkenazi (% of Jews) | 1793 (78.0) | 1607 (71.5) | 1734 (78.0) | 1607 (71.5) | ||
| Sephardi (% of Jews) | 458 (19.9) | 602 (26.8) | 444 (20.0) | 602 (26.8) | ||
| Mixed (% of Jews) | 49 (2.1) | 40 (1.8) | 46 (2.1) | 40 (1.8) | ||
| Levothyroxine use for ≥5 y | 77 (3.0) | 129 (5.1) | <.001 | 74 (3.0) | 129 (5.1) | <.001 |
| Family history of CRC among first-degree relatives | 304 (12.0) | 204 (8.1) | <.001 | 295 (12.0) | 204 (8.1) | <.001 |
| Sports activity | 769 (29.9) | 1063 (41.5) | <.001 | 750 (30.1) | 1063 (41.5) | <.001 |
| Vegetable intake of ≥5 servings per day | 1402 (56.5) | 1552 (60.9) | .002 | 1359 (56.5) | 1552 (60.9) | .002 |
| Aspirin use daily for ≥3 y | 371 (14.5) | 584 (22.9) | <.001 | 364 (14.6) | 584 (22.9) | <.001 |
| Statin use for ≥5 y | 173 (6.8) | 293 (12.5) | <.001 | 168 (6.8) | 293 (12.5) | <.001 |
| Ever HRT use (% of all women) | 70 (6.6) | 126 (10.8) | .001 | 69 (6.8) | 126 (10.8) | .001 |
Case patients were incident CRC patients and control subjects were members of the general population matched by year of birth, sex, residence (defined by primary clinic location), and ethnic group (Jewish vs non-Jewish). The 3- and 5-year cut points for use of aspirin, levothyroxine, and statin were selected to capture long-term use. Percentage discrepancies are because of missing values in some of the variables. CRC = colorectal cancer; HRT = hormone replacement therapy.
P values for comparison between case patients and control subjects calculated using the two-sided χ2 test and the t test for age.