Table 1. Participant Characteristics.* .
| Variables | Analytic Sample (N = 1640) | Unadjusted Odds Ratio (95% CI) | P-value | Adjusted Odds Ratio** (95% CI) | P-value | SHS Cohort (N = 2268) | ||
| Cases N (%) | Controls N (%) | Cases N (%) | Controls N (%) | |||||
| Gender | ||||||||
| Female | 526 (60.1) | 442 (57.8) | Ref | Ref | 699 (59.9) | 656 (59.6) | ||
| Male | 349 (39.9) | 323 (42.2) | 0.91 (0.75–1.11) | 0.34 | 1.21 (0.95–1.53) | 0.12 | 468 (40.1) | 445 (40.3) |
| Age (Mean) | 46.5 | 46.2 | 0.12 | 1.03 (1.02–1.04) | <0.01 | 46.2 | 45.8 | |
| Eye color | ||||||||
| Brown | 176 (20.1) | 187 (24.4) | Ref | Ref | 226 (19.4) | 278 (25.2) | ||
| Hazel | 179 (20.5) | 158 (20.7) | 1.20 (0.90–1.62) | 0.22 | 0.88 (0.65–1.20) | 0.43 | 237 (20.3) | 236 (21.4) |
| Green | 136 (15.5) | 102 (13.3) | 1.42 (1.02–1.97) | 0.04 | 0.97 (0.66–1.41) | 0.86 | 175 (15.0) | 142 (12.9) |
| Blue/Grey | 384 (43.9) | 318 (41.6) | 1.28 (1.00–1.65) | 0.05 | 1.00 (0.72–1.40) | 0.98 | 529 (45.3) | 445 (40.4) |
| Hair Color | ||||||||
| Dark brown/black | 217 (24.8) | 268 (35.0) | Ref | Ref | 289 (24.8) | 391 (35.5) | ||
| Light brown | 305 (34.9) | 308 (40.3) | 1.22(0.96–1.55) | 0.10 | 1.11 (0.84–1.45) | 0.46 | 396 (33.9) | 438 (39.8) |
| Blonde | 260 (29.7) | 163 (21.3) | 1.97 (1.51–2.57) | <0.01 | 1.79 (1.30–2.46) | <0.01 | 362 (31.0) | 226 (20.5) |
| Red | 93 (10.6) | 26 (3.4) | 4.42 (2.76–7.07) | <0.01 | 4.38 (2.50–7.67) | <0.01 | 120 (10.3) | 46 (4.2) |
| Skin Color | ||||||||
| Dark olive to black | 6 (0.7) | 25 (3.3) | Ref | Ref | 11 (0.9) | 36 (3.3) | ||
| Light olive | 82 (9.4) | 128 (16.7) | Ref (combined) | Ref (combined) | 114 (9.8) | 191 (17.3) | ||
| Fair | 634 (72.5) | 521 (68.1) | 2.12 (1.59–2.82) | <0.01 | 1.57(1.12–2.18) | 0.01 | 827 (70.9) | 746 (67.8) |
| Very fair | 153 (17.5) | 91 (11.9) | 2.92 (2.02–4.23) | <0.01 | 1.96 (1.26–3.06) | <0.01 | 215 (18.4) | 128 (11.6) |
| Freckling | ||||||||
| None | 404 (46.3) | 453 (59.5) | Ref | Ref | 547 (47.1) | 635 (58.0) | ||
| Very few | 257 (29.4) | 195 (25.6) | 1.48 (1.18–1.86) | <0.01 | 1.30 (1.01–1.68) | 0.04 | 326 (28.1) | 278 (25.4) |
| Few | 145 (16.6) | 82 (10.8) | 1.98 (1.47–2.68) | <0.01 | 1.35 (0.96–1.90) | 0.09 | 196 (16.9) | 127 (11.6) |
| Some/Many | 67 (7.7) | 31 (4.1) | 2.42 (1.55–3.79) | <0.01 | 1.43 (0.84–2.45) | 0.19 | 93 (8.0) | 55 (5.0) |
| Moles | ||||||||
| None | 144 (16.5) | 292 (38.2) | Ref | Ref | 191 (16.5) | 446 (40.7) | ||
| Few | 492 (56.2) | 393 (51.4) | 2.54 (2.00–3.23) | <0.01 | 2.84 (2.18–3.69) | <0.01 | 644 (55.7) | 545 (49.8) |
| Some/Many | 239 (27.3) | 80 (10.4) | 6.06 (4.39–8.36) | <0.01 | 7.22 (5.05–10.30) | <0.01 | 321 (27.7) | 104 (9.5) |
| Lifetime Sunburns | ||||||||
| None | 17 (1.9) | 42 (5.5) | Ref | Ref | 33 (2.8) | 68 (6.2) | ||
| 1–2 | 119 (13.6) | 147 (19.3) | 2.00 (1.08–3.69) | 0.03 | 1.26 (0.65–2.46) | 0.49 | 168 (14.4) | 221 (20.1) |
| 3–5 | 174 (19.9) | 143 (18.7) | 3.01 (1.64–5.51) | <0.01 | 1.66 (0.85–3.21) | 0.13 | 224 (19.2) | 215 (19.6) |
| >5 | 564 (64.5) | 431 (56.5) | 3.23 (1.81–5.76) | <0.01 | 1.60 (0.85–3.01) | 0.15 | 739 (63.5) | 595 (54.1) |
| Indoor UV exposure | ||||||||
| Never | 326 (37.6) | 377 (50.4) | Ref | Ref | 433 (39.8) | 538 (53.0) | ||
| ≤10 hours | 256 (29.5) | 206 (27.5) | 1.44 (1.14–1.82) | <0.01 | 1.40 (1.07–1.83) | 0.01 | 274 (25.2) | 243 (23.9) |
| >10 hours | 285 (32.9) | 165 (22.1) | 2.00 (1.57–2.55) | <0.001 | 2.32 (1.73–3.11) | <0.01 | 382 (35.1) | 234 (23.1) |
*For some of the variables, the total count does not equal 1640 due to a small number of missing values.
** Adjusted for gender, age, eye color, hair color, skin color, freckling, moles, lifetime sunburns, and hours of indoor tanning.