Table 2

Distributions of the D-12, CAT and E-RS total scores

D-12 score (0–36)CAT score (0–40)E-RS Total score (0–40)
MeanMedianSDMax.Floor effect (%)MeanMedianSDMax.Floor effect (%)MeanMedianSDMax.Floor effect (%)
All subjects0.
Healthy non-smoking subjects*†
COPD defined by fixed ratio0.
Non-COPD smokers0.
Non-COPD never smokers0.
COPD defined by LLN0.
Non-COPD smokers0.
Non-COPD never smokers0.
  • *FEV1 of >85% predicted and FEV1/FVC of >0.7.

  • †A smoking history of <1 pack-year. Numbers in parentheses indicate the theoretical score range, and higher scores indicate worse status.

  • CAT, COPD assessment test; COPD, chronic obstructive pulmonary disease; D-12, Dyspnoea-12; E-RS, evaluating respiratory symptoms in COPD; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; LLN, lower limit of normal.