Table 2. Baseline characteristics of the cohorts used in the study.
| (A) Baseline characteristics of UKCTOCS cohorts used for the discovery and validation studies | ||||||
|---|---|---|---|---|---|---|
| |
Discovery set, median (25th–75th centiles) |
Validation set, median (25th–75th centiles) |
||||
| Controls (N=273) | Breast cancer cases (N=240) | Controls and BC (N=513) | Controls (N=431) | Breast cancer cases (N=431) | Controls and BC (N=862) | |
| Age (years) at randomisation |
60 (55–65) |
60 (56–66) |
60 (56–65) |
61 (55–66) |
61 (57–66) |
61 (57–66) |
| Years since last period at randomisation |
11 (5–19) |
10 (5–17) |
11 (5–18) |
12 (6–18) |
11 (5–18) |
11(6–18) |
| Duration of HRT use in those who were on HRT at randomisation (years) |
8 (5–12) |
8 (5–11) |
8 (5–12) |
8 (5–12) |
11 (6–13) |
10 (5–13) |
| Duration of OCP use (years) in those who had used it |
6 (3–10) |
6 (2–10) |
6 (3–10) |
5 (2–10) |
5 (2–10) |
5 (2–10) |
| Height (cms) |
163 (156–165) |
163 (158–168) |
163 (158–168) |
163 (158–165) |
163 (158–168) |
163 (158–168) |
| Weight (kg) | 67 (60–76) | 69 (63–76) | 68 (61–76) | 66 (60–76) | 68 (61–76) | 68 (60–76) |
| Ethnicity | Number (%) | Number (%) | ||||
|---|---|---|---|---|---|---|
| White | 262 (95·8%) | 234 (97·5%) | 496 (96.7%) | 417 (96·6%) | 426 (98·8%) | 843 (97·8%) |
| Other | 9 (3·3%) | 6 (2·5%) | 15 (2·9%) | 13 (3·0%) | 4 (0·9%) | 17 (2·0%) |
| Missing |
2(0·8%) |
0 (0%) |
2 (0·4%) |
1 (0·2%) |
1 (0·2%) |
2 (0·2%) |
| Hysterectomy |
51 (19·2%) |
46 (19·2%) |
97 (18.9%) |
75 (17·4%) |
83 (19·3%) |
158 (18·3%) |
| Ever use of OCP |
144 (53·3%) |
138 (57.5%) |
282 (55.0%) |
258 (59·8%) |
276 (64·0%) |
534 (62·0%) |
| Use of HRT at recruitment |
70 (26.3%) |
55 (23·0%) |
125 (24·6%) |
72 (16·7%) |
142 (33·0%) |
214 (24·9%) |
| Women having 1 or more pregnancies |
235 (85·4%) |
203 (84·6%) |
438 (85·4%) |
388 (90.0%) |
374 (86.8%) |
762 (88.4%) |
| Women having 1 or more miscarriages | 73 (25·8%) | 62 (25·8%) | 135 (26.3%) | 114 (26.55) | 131 (30.4%) | 245 (28.4%) |
| (B) Baseline characteristics of breast cancer cases and controls from the Guernsey cohort used in the Validation study | |||
|---|---|---|---|
| |
Median (25th–75th centiles) |
||
| Controls (N=664) | Breast cancer cases (N=332) | Controls and BC (N=996) | |
| Age (years) at serum donation |
50 (42–58) |
50 (43–57) |
50 (42–58) |
| Duration of HRT use in those who were on HRT at time of serum donation (years) |
7(3–20) |
11 (4–30) |
8 (3–23) |
| Duration of OCP use (years) in those who had used it |
3.8 (1–7.3) |
4(1–9.6) |
3.9 (1–9.6) |
| Height (cms) |
160 (155–164) |
161 (157–165) |
160 (156–165) |
| Weight (kg) | 64 (57–70) | 64 (60–72) | 64 (58–71) |
| Number (%) | |||
|---|---|---|---|
| Ethnicity: Missing |
664 (100%) |
332 (100%) |
996 (100%) |
|
Menopausal status | |||
| Pre | 259 (39·0%) | 114 (34·3%) | 373 (37·5%) |
| Peri | 54 (8·1%) | 22 (6·6%) | 76 (7·6%) |
| Post | 249 (37·5%) | 151 (45·6%) | 400 (40·2%) |
| Hysterectomy |
102 (15·4%) |
45 (13·6%) |
147 (14·6%) |
|
Use of oral contraceptive pill | |||
| Ever | 94 (14·1%) | 51 (15·4%) | 145 (14·6%) |
| Unknown |
439 (66·1%) |
221 (66·6%) |
660 (66·3%) |
| Use of HRT at recruitment |
36 (5·4%) |
20 (6·0%) |
56 (5·6%) |
| Women having 1 or more pregnancies |
560 (84·3%) |
288 (86·7%) |
848 (85·1%) |
| Women having 1 or more miscarriages | 144 (21·7%) | 86 (25·9%) | 230 (23·1%) |
Abbreviations: HRT=hormone replacement therapy; OCP=oral contraceptive pill; UKCTOCS=UK Collaborative Trial of Ovarian Cancer Screening.