From: Headaches attributed to airplane travel: a Danish survey
AH-group
Non-AH-group
Total
Females
12 (5 %)
146 (57 %)
158 (62 %)
Males
9 (4 %)
87 (34 %)
96 (38 %)
21 (9 %)
233 (91 %)
254 (100 %)