Table 5.
Concurrent validity of the DIRECT score: Spearman correlation coefficients between patient-reported outcomes scores (n = 247)
| DIRECT score | SGRQ symptom score | SGRQ activity score | SGRQ impact score | SGRQ total score | LHS overall handicap severity score | |
|---|---|---|---|---|---|---|
| SGRQ symptom score | 0.61 | |||||
| SGRQ activity score | 0.83 | 0.56 | ||||
| SGRQ impact score | 0.83 | 0.72 | 0.78 | |||
| SGRQ total score | 0.87 | 0.78 | 0.87 | 0.97 | ||
| LHS overall handicap severity score | −0.70 | −0.45 | −0.70 | −0.65 | −0.70 | |
| MMRC dyspnea scale | 0.73 | 0.48 | 0.70 | 0.70 | 0.72 | −0.67 |
Abbreviations: LHS, London Handicap Scale; MMRC, Modified Medical Research Council; SGRQ, St Georges Respiratory Questionnaire.