Table 3.
Interaction between headache type and laterality.
| Non-classifiable headache | Migraine | Tension-type headache | Tension-type headache and migraine | Cluster headache | |
|---|---|---|---|---|---|
| Headache left | 14 | 24 | 2a | 3 | 6a |
| Headache right | 11 | 19 | 8 | 3 | 2 |
| Headache bilateral | 36 | 42 | 15 | 5 | 0a |
Chi-square of independence indicates a significant association of headache type and laterality with decreased number of left-sided tension-type and bilateral cluster headache and increased frequency of left-sided cluster headache (χ2=17.926; df = 8; p = 0.022).
aThe number of cases in this cell is significant different from the number of expected cases under the assumption of independence of variables.
< or > indicate significant post hoc contrasts.