TABLE 2

St George's Respiratory Questionnaire (SGRQ) minimal important differences (MIDs)

MethodsAbsolute SGRQ MID 1 month (unit)Relative SGRQ MID 1 month (%)Absolute SGRQ MID 6 months (unit)Relative SGRQ MID 6 months (%)
Anchor-based
 RV−8.7−13.8−6.4−10.2
 FEV1−9.2−13.0−7.8−11.5
 6MWD−8.5−15.3−6.3−9.2
Distribution-based−6.9−11.37.9−13.3
Combined−8.3−13.4−7.1−11.1
  • Data are presented as SGRQ units or percentage change compared with baseline. RV: residual volume; FEV1: forced expiratory volume in 1 s; 6MWD: 6-min walk distance.