A summary of epidemiological characteristics of the subjects included in the nested case–control study
| Controls | Cases | P_difference* | |
| Women (n) | 1428 | 750 | |
| Age at baseline (%) | 0.70 | ||
| <60 | 496 (34.7%) | 256 (34.1%) | |
| 60–69 | 701 (49.1%) | 381 (50.8%) | |
| ≥70 | 231 (16.2%) | 113 (15.1%) | |
| Age at censoring (%) | <0.0001 | ||
| <60 | 50 (3.5%) | 107 (14.3%) | |
| 60–69 | 388 (27.2%) | 354 (47.2%) | |
| 70–79 | 681 (47.7%) | 275 (36.7%) | |
| ≥80 | 309 (21.6%) | 14 (1.9%) | |
| Birth cohort (%) | 0.76 | ||
| <1930 | 28 (2.0%) | 10 (1.3%) | |
| 1930–1939 | 639 (44.7%) | 339 (45.2%) | |
| 1940–1949 | 669 (46.8%) | 354 (47.2%) | |
| ≥1950 | 92 (6.4%) | 47 (6.3%) | |
| Mean age at baseline (SD) | 63 (6.2) | 63 (6.2) | |
| Mean censored age (SD) | 74 (7.1) | 68 (6.6) | |
| Mean PRS (SD) | |||
| Overall | −0.47 (0.27) | −0.39 (0.27) | |
| Serous | −0.55 (0.35) | −0.43 (0.36) | |
| Family history of ovarian cancer (%) | |||
| Considering only first-degree relatives | 0.088 | ||
| Zero affected relatives | 1387 (97.1%) | 718 (95.7%) | |
| One affected relative | 41 (2.9%) | 32 (4.3%) | |
| Considering both first-degree and second- degree relatives | 0.15 | ||
| Zero affected relatives | 1356 (95.0%) | 701 (93.5%) | |
| One or more affected relatives | 72 (5.0%) | 49 (6.5%) | |
| Morphology/histotype (%) | |||
| Serous | 489 (65.2%) | ||
| High grade | 417 (55.6%) | ||
| Low grade | 23 (3.1%) | ||
| Missing | 49 (6.5%) | ||
| Clear cell | 29 (3.9%) | ||
| Endometrioid | 56 (7.5%) | ||
| Mucinous | 24 (3.2%) | ||
| Others | 152 (20.3%) | ||
*χ2 tests for differences in the distributions between cases and controls.