Table 2.
Results of logistic regression in Sample I.
| Explanatory variables | Patients n (%) |
Controls n (%) |
Adjusted odds ratio†
(95% CI) |
P # (R 2+)§ |
|---|---|---|---|---|
| Sample I | 53 | 136 | ||
|
| ||||
| Hair color | ||||
| Dark brown to brown | 12 (22.6) | 60 (44.1) | 1.0 | 0.001 (5.60) |
| Light brown to dark blond | 20 (37.8) | 64 (47.1) | 3.11 (0.86–11.27) | |
| Blond to strawberry blonde/red | 21 (39.6) | 12 (8.8) | 23.50*** (3.99–138.24) | |
| Eye color | ||||
| Dark color | 21 (39.6) | 56 (41.2) | 1.0 | 0.40 (0.30) |
| Mixed color | 10 (18.8) | 31 (22.8) | 1.07 (0.29–3.96) | |
| Light color | 22 (41.6) | 49 (36.0) | 0.59 (0.18–1.96) | |
†Odds ratios were adjusted for age, sex, and smoking (P values for these covariates were 0.001, 0.040, and 0.114, resp.); # P for trend; §explained variance (%) by the respective variable (Nagelkerke R 2+); *significance for odds ratios: ***P < 0.001.