Table 2.
Frequency distribution of participant characteristics by racial/ethnic group
| Participant characteristics | Race/ethnicity |
|||||||
|---|---|---|---|---|---|---|---|---|
| Non-Hispanic White |
Hispanic |
Black |
Asian/Pacific Islander |
|||||
| Cases (n = 8918) |
Controls (n = 13619) |
Cases (n = 433) |
Controls (n = 533) |
Cases (n = 911) |
Controls (n = 1233) |
Cases (n = 662) |
Controls (n = 765) |
|
| n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | |
| Age | ||||||||
| 18–50 years | 2242 (25) | 4355 (32) | 155 (36) | 286 (54) | 245 (27) | 439 (36) | 310 (47) | 344 (45) |
| 51–60 years | 2923 (33) | 4385 (32) | 142 (33) | 147 (27) | 294 (32) | 430 (35) | 162 (25) | 197 (26) |
| ≥61 years | 3753 (42) | 4879 (36) | 136 (31) | 100 (19) | 372 (41) | 364 (29) | 190 (29) | 224 (30) |
| Parity | ||||||||
| 0 live births | 2230 (25) | 2240 (16) | 84 (19) | 73 (14) | 164 (18) | 166 (13) | 220 (33) | 151 (20) |
| 1 live birth | 1250 (14) | 1797 (13) | 65 (15) | 73 (14) | 163 (18) | 237 (19) | 118 (18) | 128 (17) |
| 2 live births | 2689 (30) | 4802 (35) | 93 (21) | 139 (26) | 209 (23) | 339 (28) | 167 (25) | 246 (32) |
| ≥3 live births | 2749 (31) | 4790 (35) | 191 (44) | 248 (46) | 375 (41) | 491 (40) | 157 (24) | 240 (31) |
| Duration of oral contraceptive use | ||||||||
| Never used | 3521 (40) | 3623 (27) | 224 (52) | 202 (38) | 311 (34) | 306 (25) | 437 (66) | 385 (50) |
| <5 years | 3132 (35) | 4819 (35) | 139 (32) | 198 (37) | 363 (40) | 526 (43) | 165 (25) | 232 (30) |
| ≥5 years | 2265 (25) | 5177 (38) | 70 (16) | 133 (25) | 237 (26) | 401 (32) | 60 (9) | 148 (19) |
| Family history of ovarian/breast cancera | ||||||||
| No | 7065 (79) | 11409 (84) | 363 (84) | 476 (89) | 677 (74) | 1041 (84) | 589 (89) | 680 (89) |
| Yes | 1853 (21) | 2210 (16) | 70 (16) | 57 (11) | 234 (26) | 192 (16) | 73 (11) | 85 (11) |
| Recent BMIb | ||||||||
| Normal (<25 kg/m2) | 3518 (48) | 5458 (50) | 140 (37) | 201 (43) | 161 (18) | 238 (21) | 382 (73) | 445 (74) |
| Overweight (25–29.9 kg/m2) | 2117 (29) | 3159 (29) | 125 (33) | 151 (32) | 243 (27) | 325 (28) | 108 (20) | 126 (21) |
| Obese (≥30 kg/m2) | 1739 (23) | 2328 (21) | 113 (30) | 116 (25) | 485 (55) | 594 (51) | 35 (7) | 33 (5) |
| Missing | 132 | 54 | 6 | 3 | 5 | 7 | 9 | 8 |
| Hysterectomyc | ||||||||
| No | 7176 (81) | 11304 (83) | 362 (84) | 478 (90) | 599 (66) | 957 (78) | 595 (90) | 707 (93) |
| Yes | 1705 (19) | 2273 (17) | 70 (16) | 54 (10) | 310 (34) | 273 (22) | 66 (10) | 57 (7) |
| Missing | 37 | 42 | 1 | 1 | 2 | 3 | 1 | 1 |
| Tubal ligationd | ||||||||
| No | 6983 (82) | 9732 (75) | 332 (83) | 383 (75) | 614 (68) | 747 (61) | 565 (88) | 620 (82) |
| Yes | 1536 (18) | 3310 (25) | 69 (17) | 127 (25) | 294 (32) | 483 (39) | 76 (12) | 136 (18) |
| Missing | 60 | 82 | 0 | 2 | 3 | 3 | 0 | 1 |
| Age at menarche | ||||||||
| <12 years | 1824 (21) | 2779 (21) | 104 (24) | 143 (27) | 223 (25) | 329 (27) | 124 (19) | 163 (21) |
| 12–13 years | 4881 (55) | 7477 (55) | 220 (51) | 245 (46) | 457 (50) | 593 (48) | 315 (48) | 365 (48) |
| ≥14 years | 2134 (24) | 3265 (24) | 108 (25) | 144 (27) | 230 (25) | 311 (25) | 214 (33) | 234 (31) |
| Missing | 79 | 98 | 1 | 1 | 1 | 0 | 9 | 3 |
| History of endometriosis | ||||||||
| No | 6675 (89) | 10115 (92) | 359 (94) | 447 (95) | 809 (91) | 1113 (96) | 461 (87) | 566 (93) |
| Yes | 790 (11) | 845 (8) | 21 (6) | 22 (5) | 81 (9) | 49 (4) | 67 (13) | 44 (7) |
| Missing | 41 | 39 | 4 | 2 | 4 | 2 | 6 | 2 |
| Education | ||||||||
| Less than high school | 839 (10) | 790 (6) | 115 (35) | 103 (26) | 129 (15) | 147 (12) | 70 (11) | 67 (9) |
| ≥High school graduate | 7473 (90) | 11884 (94) | 210 (65) | 290 (74) | 734 (85) | 1048 (88) | 573 (89) | 675 (91) |
| Missing | 606 | 945 | 108 | 140 | 48 | 38 | 19 | 23 |
| Body powder use | ||||||||
| Never use | 3273 (53) | 5447 (59) | 220 (64) | 311 (73) | 354 (42) | 537 (50) | 313 (75) | 366 (74) |
| Any genital use | 1876 (30) | 2227 (24) | 60 (18) | 65 (15) | 344 (40) | 335 (31) | 36 (9) | 38 (8) |
| Body/non-genital use | 1029 (17) | 1500 (16) | 61 (18) | 50 (12) | 150 (18) | 203 (19) | 70 (17) | 90 (18) |
| Missing | 621 | 837 | 5 | 7 | 38 | 55 | 91 | 104 |
| Breastfeedinge | ||||||||
| No | 2831 (44) | 3817 (35) | 170 (52) | 219 (50) | 500 (67) | 650 (61) | 123 (29) | 143 (24) |
| Yes | 3601 (56) | 7140 (65) | 154 (48) | 220 (50) | 247 (33) | 417 (39) | 306 (71) | 465 (76) |
| Aspirin usef | ||||||||
| No | 4173 (80) | 6132 (79) | 145 (82) | 172 (88) | 604 (85) | 878 (85) | 229 (87) | 231 (81) |
| Yes | 1051 (20) | 1625 (21) | 32 (18) | 23 (12) | 110 (15) | 155 (15) | 35 (13) | 53 (19) |
| Missing | 2282 | 3242 | 207 | 276 | 180 | 131 | 270 | 328 |
| Acetaminophen usef | ||||||||
| No | 4316 (80) | 6358 (80) | 155 (87) | 169 (87) | 621 (84) | 909 (86) | 234 (88) | 245 (86) |
| Yes | 1062 (20) | 1554 (20) | 23 (13) | 25 (13) | 116 (16) | 148 (14) | 32 (12) | 39 (14) |
| Missing | 2128 | 3087 | 206 | 277 | 157 | 107 | 268 | 328 |
| NSAID usef | ||||||||
| No | 3881 (73) | 5655 (72) | 125 (73) | 148 (79) | 546 (74) | 777 (74) | 221 (85) | 246 (88) |
| Yes | 1428 (27) | 2164 (28) | 47 (27) | 39 (21) | 191 (26) | 280 (26) | 39 (15) | 34 (12) |
| Missing | 2197 | 3180 | 212 | 284 | 157 | 107 | 274 | 332 |
| Hormone therapy useg | ||||||||
| No | 3163 (49) | 4122 (47) | 171 (61) | 160 (61) | 474 (73) | 574 (74) | 211 (58) | 211 (54) |
| Yes | 3266 (51) | 4703 (53) | 110 (39) | 103 (39) | 171 (27) | 202 (26) | 153 (42) | 180 (46) |
| Missing | 37 | 48 | 2 | 1 | 5 | 2 | 0 | 0 |
| Any estrogen-only therapy useg | ||||||||
| No | 2480 (65) | 3523 (65) | 158 (72) | 143 (77) | 468 (79) | 554 (83) | 187 (76) | 186 (71) |
| Yes | 1311 (35) | 1865 (35) | 61 (28) | 43 (23) | 121 (21) | 114 (17) | 59 (24) | 76 (29) |
| Missing | 1212 | 2109 | 37 | 43 | 49 | 63 | 71 | 97 |
| Histology | ||||||||
| Serous | ||||||||
| High-grade seroush | 6060 (68) | 303 (70) | 669 (76) | 341 (52) | ||||
| Low-grade serous | 288 (3) | 23 (5) | 27 (3) | 4 (1) | ||||
| Mucinous | 455 (5) | 38 (9) | 52 (6) | 77 (12) | ||||
| Endometrioid (low-grade) | 532 (6) | 18 (4) | 26 (3) | 45 (7) | ||||
| Clear cell | 609 (7) | 17 (4) | 28 (3) | 120 (18) | ||||
| Mixed | 296 (3) | 3 (1) | 11 (1) | 13 (2) | ||||
| Other or unspecified epithelial | 660 (7) | 31 (7) | 69 (8) | 61 (9) | ||||
| Missing | 164 | 0 | 29 | 1 | ||||
| Stage | ||||||||
| Localized | 1364 (18) | 81 (19) | 147 (18) | 195 (33) | ||||
| Regional | 1307 (17) | 67 (16) | 130 (15) | 126 (21) | ||||
| Distant | 5053 (65) | 279 (65) | 558 (67) | 275 (46) | ||||
| Missing | 107 | 6 | 75 | 11 | ||||
Number of participants with missing data was determined from only those sites that provided data for that covariate. The following variables were not available or considered missing for certain sites: body powder exposure (CON, OVA, STA, UCI); endometriosis (OVA, STA); analgesic medications (OVA, STA); BMI (OVA, STA); tubal ligation (UCI); breastfeeding (UCI); estrogen-only hormone therapy use (AUS, CON, STA); stage (OVA).
aFamily history of ovarian/breast cancer in a first-degree relative.
bRecent BMI is defined as BMI 1 year before reference date (interview date for controls and diagnosis date for cases) for AAS, AUS, HOP, NCO, NEC, UCI and USC or 5 years before reference date for CON, DOV and HAW.
cHysterectomy that occurred at least 1 year before the reference date.
dTubal ligation that occurred at least 1 year before the reference date.
eBreastfeeding was assessed among women who had one or more live births.
fAnalgesic medication use was defined as use at least once a week. Three sites had missing data on analgesic medications for specific ascertainment periods: HAW did not collect data on analgesic medications between 1993 and 1999, NCO did not collect data on aspirin use for the first 2 years of the study and USC only provided data on analgesic medications collected during 2000–05.
gHormone therapy use was assessed among postmenopausal women.
hHGSOC was defined as any patient diagnosed with serous histology and tumour grade ≥2 or missing, endometrioid histology and grade ≥2, and undifferentiated/poorly differentiated EOC with unspecified histology and grade ≥2.