Abstract
Background:The Hospital Anxiety and Depression Scale is widely used to screen for anxiety and depression. A cut-off of 8 offers the best sensitivity and specificity for identifying a mood disorder. The minimum important difference (MID) for domain scores has not been estimated in COPD.
Aim:To estimate the MID for anxiety (HADS-A) and depression (HADS-D) domains in COPD patients at risk of anxiety and depression (domain scores ≥8).
Methods:HADS,St. George's Respiratory Questionnaire (SGRQ),Chronic Respiratory Questionnaire (CRQ),Clinical COPD Questionnaire (CCQ) and global rating of change questionnaire (GRCQ) were measured pre and post pulmonary rehabilitation in COPD patients;HADS-A (n=337) and D (n=294) ≥8 at baseline. Distribution and anchor-based approaches were used to estimate the MID.
Results:Mean(95%CI) change in HADS-A was -2.3(-2.6,-1.9) and correlated with change in CRQ-F,CRQ-E,CRQ-M and CRQ-Total (r=-0.34,-0.49,-0.34,-0.45). Change in HADS-D was -2.4(-2.7,-2.0) and correlated with change in CRQ-F,CRQ-E,CRQ-M,CRQ-Total,SGRQ-I,SGRQ-Total and CCQ-Total (r=-0.37,-0.41,-0.37,-0.46,0.33,0.38,0.34). Estimates of the MID are in Table 1.
Conclusion:The individual level MID is -2 (HADS-A) and -3 (HADS-D). Population–level MID estimates were –1.6 to –2.1 (HADS-A) and –1.8 to –2.1 (HADS-D).
- © 2014 ERS