Table 5 Pearson's correlation between the new index score with other variables.
| Variables | Pearson's correlation, r | p Value |
|---|---|---|
| SAFE Index vs FEV1 | −0.807 | <0.001 |
| SAFE Index vs FEV1%Pred | −0.710 | <0.001 |
| SAFE Index vs 6MWD | −0.621 | <0.001 |
| SGRQ indices | ||
| SAFE Index vs symptom score | 0.604 | <0.001 |
| SAFE Index vs activity score | 0.816 | <0.001 |
| SAFE Index vs impact score | 0.763 | <0.001 |
| SAFE Index vs total score | 0.801 | <0.001 |
| SAFE Index vs 2 year exacerbation rate | 0.497 | <0.001 |
FEV1%Pred, percentage of predicted forced expiratory volume in 1 s; 6MWD, 6 min walk distance; SGRQ, St George's Respiratory Questionnaire.