Results of multivariate logistic regression model comparing post-traumatic headache with cluster headache phenotype (n=21) and primary cluster headache (control cohort; n=553)
| Predictive factor | OR | 95% CI | P value |
| Family history of cluster headache | 3.32 | 1.31 to 8.63 | 0.012 |
| Chronic cluster headache phenotype | 3.29 | 1.70 to 6.49 | <0.001 |
| Temporal location | 2.04 | 1.10 to 3.84 | 0.024 |
| Parietal location | 14.82 | 6.32 to 37.39 | <0.001 |
| Presence of eye oedema | 5.79 | 2.57 to 13.82 | <0.001 |
| Presence of miosis | 11.24 | 3.21 to 41.34 | |
| Presence of rhinorrhoea | 2.65 | 1.26 to 5.86 | 0.013 |
| Presence of facial sweating | 2.53 | 1.33 to 4.93 | 0.005 |
| Restlessness | 4.63 | 1.16 to 22.19 | 0.039 |
| Associated chronic migraine | 10.35 | 3.96 to 28.82 | <0.001 |
| Intractable to acute treatment | 12.34 | 2.51 to 64.73 | 0.002 |
| Intractable to preventive treatment | 16.98 | 6.88 to 45.52 | <0.001 |