Table 1 The modified Medical Research Council (mMRC) scale

Grade 0

I only get breathless with strenuous exercise

Grade 1

I get short of breath when hurrying on level ground or walking up a slight hill

Grade 2

On level ground, I walk slower than people of the same age because of breathlessness, or I have to stop for breath when walking at my own pace on the level

Grade 3

I stop for breath after walking about 100 yards or after a few minutes on level ground

Grade 4

I am too breathless to leave the house or I am breathless when dressing