Table 3 Multivariable* risk factors for headache chronicity in patients with episodic migraine
| Risk factors | Odds ratio | 95% CI | p Value |
|---|---|---|---|
| * Adjusted for all other variables in the model. | |||
| Headache frequency 5–9 d | 6.2 | 1.7–26.6 | 0.005 |
| Headache frequency >10 d | 20.1 | 5.7–71.5 | 0.001 |
| Overuse | 19.4 | 8.7–43.2 | 0.001 |