Table 1.

Lake louise acute mountain sickness scoring system

Self reported symptoms: (Score)
Headache:	no (0), mild (1), moderate (2), severe, incapacitating (3)
Gastrointestinal:	no (0), poor appetite or nausea (1), moderate nausea or nausea (2), severe nausea and vomiting, incapacitating (3)
Fatigue and/or weakness:	no (0), mild (1), moderate (2), severe (3)
Dizziness or light headedness:	no (0), mild (1), moderate (2), severe, incapacitating (3)
Difficulty to sleep:	as well as usual (0), not as well as usual (1), poor night sleep, woke up many times (2), could not sleep at all (3)
Clinical assessment: (Score)
Change in mental status:	no (0), lethargy or lassitude (1), disorientated or confused (2), stupor or semi-consciousness (3), coma (4)
Ataxia (heel-to-toe walking):	no (0), manoeuvres to maintain balance (1), steps off line (2), falls down (3), cannot stand (4)
Peripheral edema:	no (0), at one location (1), at two or more locations (2),
If you have any symptoms how do they affect your activity?:	no reduction (0), mild (1), moderate (2), severe reduction, e.g bed rest (3)

The scoring system tries to quantify the severity of acute mountain sickness (AMS). A score (sum of the points) of 3 or more on the self-reported symptoms section, or for the combined self-reported questionnaire and clinical assessment of more than 3, while at altitude above 2,500 m, indicates AMS.