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Table 7 Minimal important differences (MID)

From: Psychometric properties and minimal important differences of SF-36 in Idiopathic Pulmonary Fibrosis

   PCS MCS PFI ROLEM ROLPH GHP MHI VITAL SOCIAL PAIN
Distribution based           
  1/2 sd 5.2 5.9 13.9    9.2 10.6 9.4 14.3 14.1
Anchor based via linking           
  FVC 5.3   14.1   20.5      
  DLCO 8.4   22.2   32.3      
  6MWD 2.6   6.9   10.1    4.7 7.1  
MID Rangea 2.6–8.4 5.9 10.1–22.2   10.1–32.3 9.2 10.6 4.7–9.4 7.1–14.3 14.1
  mean alla 5 6 14   21 9 11 7 11 14
  mean selectedb 4 6 10   10 9 11 7 11 14
  1. a based on anchor (if estimate is significant, r ≥ 0.3 or R2 ≥ 0.09) and distribution based MID (in case of normal distribution)
  2. b based on anchor with the highest correlation (if estimate is significant, r ≥ 0.3 or R2 ≥ 0.09) and distribution based MID (in case of normal distribution)
  3. Abbreviations: sd standard error, SEM Standard error of the mean, FVC pred forced vital capacity percent predicted, DLCO pred diffusing capacity of the lungs for carbon monoxide percent predicted, 6MWD 6 min walking distance, PCS Physical component score, MCS Mental component score, GHP General health perceptions, PFI Physical functioning, ROLPH physical role functioning, ROLEM emotional role functioning, SOCIAL Social role functioning, MHI Mental health, PAIN bodily pain, VITAL vitality