Table 1. Classification and scoring criteria of the symptoms of high-altitude de-acclimatization syndrome.

Classification	Judgment standards	Scoring standards
±	Mild symptoms with no impact on daily life	0
+	Mild symptoms with slight impact on daily life, ameliorated after drug regimen	1
++	Severe symptoms affect daily life, somewhat alleviated after drug regimen	2
+++	Severe symptoms affect daily life, no significant relief after drug regimen	3