Table 1.
ICHD-3 criteria for 9.2.2 headache attributed to systemic viral infection.
| Criterion | Frequency |
|---|---|
| A. Headache of any duration fulfilling criterion C | |
| B. Both of the following: | 106 (100%) |
| 1. Systemic viral infection has been diagnosed | 106 (100%) |
| 2. No evidence of meningitic or encephalitic involvement | 106 (100%) |
| C. Evidence of causation demonstrated by at least two of the following: | 100 (94.3%) |
| 1. Headache has developed in temporal relation to onset of the systemic viral infection | 78 (73.6%) |
| 2. Headache has significantly worsened in parallel with worsening of the systemic viral infection | 42 (39.6%) |
| 3. Headache has significantly improved or resolved in parallel with improvement or resolution of the systemic viral infection | 58 (54.7%) |
| 4. Headache has either or both of the following characteristics: | (99.1%) |
| 4a. Diffuse pain | (54.7%) |
| 4b. Moderate or severe intensity | 102 (96.2%) |
| D. Not better accounted for by another ICHD-3 diagnosis | 106 (100%) |
ICHD-3: The International Classification of Headache Disorders, 3rd edition.