This example shows results from a randomized controlled trial comparing intensive respiratory rehabilitation to conventional care in patients with moderate to severe chronic respiratory disease. The lines depict change scores on the seven-point CRQ dyspnea domain. Because HRQL in patients with COPD deteriorates over time, the mean CRQ dyspnea score decreased (worse function) in the control group after three months of observation. Patients in the rehabilitation group showed a small increase in CRQ scores. The mean difference between the two groups was 0.6 (95% confidence interval = 0.18 to 1.03). The figure indicates that a greater proportion of patients in the treatment compared to the control group had an improvement greater than the MID. One can calculate the proportion of patients improving in both groups that improve above or below any threshold.