Table 7

MID Estimates for the QOL-B scales

QOL-B V.3.0 scale and method of estimating MIDMIDnMIDn
Respiratory Symptoms8.0
 1/2 SD‡8.02667.7274
Physical Functioning10.0
 1/2 SD‡10.12669.9274
 1/2 SD‡9.52669.4274
Role Functioning8.0
 1/2 SD‡8.62668.2274
Health Perceptions8.0
 1/2 SD‡8.22667.9274
Emotional Functioning7.0
 1/2 SD‡7.12666.8274
Social Functioning9.0
 1/2 SD‡7.82667.3274
Treatment Burden9.0
 1/2 SD‡9.824710.0232
  • *Final MIDs were the average of the 6 MID values obtained for each scale, rounded to the nearest integer.

  • †Anchor-based MID=mean change from baseline QOL-B score at day 14 for patients with minimal change on the corresponding GRCQ (>0.5 to 1.5 improvement or worsening of scores on −3 to 3 scale).

  • ‡1/2 SD of mean change from baseline QOL-B score at day 14.

  • §SEM for baseline scores; SEM=SD√(1-α), with SD of mean baseline score and α=Cronbach's α.

  • GRCQ, Global Rating of Change Questionnaire; MID, minimal important difference; QOL-B, Quality of Life-Bronchiectasis; SEM, SE of measurement.