Table 1.

Comparison of AMS and no-AMS (total n = 74) volunteers at an altitude of 3860 m

	day 1	day 2	day 3
AMS	33/74 (44.6 %)	16/74 (21.6 %)	11/74 (14.9 %)
Headache	33/33 (100 %)	16/16 (100 %)	11/11 (100 %)
No-AMS	41/74 (55.4 %)	58/74 (78.4 %)	63/74 (85.1 %)
Headache only	8/41 (19.5 %)	7/58 (12.0 %)	6/63 (14.6 %)
Headache + one symptom	9/41 (21.9 %)	9/58 (15.5 %)	3/63 (4.8 %)
Others (no-headache)	12/41 (29.2 %)	15/58 (25.9 %)	14/63 (22.2 %)
No symptom	12/41 (29.2 %)	27/58 (46.6 %)	40/63 (63.5 %)

Note: % indicates the incidence of symptom