# Table 2 Score of each anchor item, the distribution of the items and the polychoric correlation of each item with NYHA classification

Raw
Score
N (%) r+
Total   N = 265
Do you usually have breathlessness or difficulty breathing? ("dyspnea")   N = 263 (99.2)
Yes, when walking on steep plane 0 185 (70.3) 0.57
Yes, when walking on the horizontal plane 1 68 (25.9)
Yes, even at rest 2 10 (3.8)
If yes, how long can you walk before you have to stop?
("distance")*
N = 232 (87.5)
0-100 metres 2 97 (41.8) 0.33
101-500 metres 1 86 (37.1)
501-2500 metres 0 49 (21.1)
If yes, after how many sets of stairs (10-15 steps) do you have to stop? ("stairs")*   N = 258 (97.3)
1 set 2 93 (36.0) 0.66
2 sets 1 75 (29.1)
3 or more sets 0 90 (34.9)
If yes, in your view, what level of effort induces breathlessness? ("effort")   N = 257 (97.0)
Great efforts 0 105 (40.9) 0.67
Average efforts 1 89 (34.6)
Small efforts 2 63 (24.5)
Median (IQR)
Raw score (0-8)   4 (2-6) 0.62
1. * inverse order for the final score
2. + polychoric correlation between each item and NYHA classification of all observers
3. IQR: interquartile range.