Supplementary Table 2.

The modified Medical Research Council scale (mMRC).

	Severity	Grade
Dyspnea only with strenuous exercise	No dyspnea	0
Dyspnea when hurrying or walking up a slight hill	Slight dyspnea	1
Walks slower than people of the same age because of dyspnea or has to stop for breath when walking at own pace	Moderate dyspnea	2
Stops for breath after walking 100 yards (91m) or after a few minutes	Severe dyspnea	3
Too dyspneic to leave house or breathless when dressing	Very severe dyspnea	4