Evidence based approach to diagnosing Migraines
The pretest probability of a patient presenting to a PCP with a complain of headache to be migraine is 6-15%. A meta analysis identified nausea, photophobia, phonophobia and exacerbation with physical activity to be best individual symptoms for ruling in or out migraine. The best predictor was nausea.
Headache with nausea = increases likelihood of headache being migraine to 90%
5 Item Clinical Decision rule for Diagnosing Migraines
- Pulsatile quality of headache
- Headache lasting 4-72hrs
- Unilateral headache
- Nausea / vomiting
- Disabling intensity of headache
| No of Clinical Features | Likelihood Ratio | Probability in Men In Gen Population | Prob in Women in Gen Population | Visit to PCP with any headache |
| 0-2 | 0.41 | 2.5 | 6.7 | 17 |
| 3 | 3.5 | 18 | 38 | 64 |
| 4-5 | 24 | 60 | 81 | 92 |
References:
- Mark Ebell. Am Fam Physician. 2006 Dec 15;74(12):2087-2088
