Table 2 2 × 2 contingency table detailing the sensitivity and specificity analyses for the CDQ cut off score of 16.5 for subjects in ‘at risk’ and ‘existing’ COPD groups
From: Accuracy of the COPD diagnostic questionnaire as a screening tool in primary care
| Â | True class (COPD diagnosis with presence of obstruction confirmed by spirometry) | ||
|---|---|---|---|
True | False | Total | |
Predicted class (Score ≥ 16.5) | |||
 True | 34 (24.1%) | 63 (44.7%) | 97 (68.8%) |
 False | 8 (5.7%) | 36 (25.5%) | 44 (31.2%) |
Total | 42 (29.8%) | 99 (70.2%) | 141 (100.0%) |