The positive predictive value (PPV) and proportion of patients diagnosed with chronic obstructive pulmonary disease (COPD) within each algorithm
| Algorithm | Number of questionnaires sent out (n=951) | Number evaluable returned (n=696) (%) | Number with confirmed COPD | PPV and 95% CI |
|---|---|---|---|---|
| COPD Code+spirometry+COPD medication | 119 | 85 (71.4) | 76 | 89.4, 80.7 to 94.5 |
| COPD Code+spirometry | 119 | 79 (66.4) | 67 | 83.8, 73.7 to 90.4 |
| COPD Code+COPD medication | 119 | 88 (73.9) | 77 | 87.5, 78.6 to 93.0 |
| COPD Code only | 119 | 89 (74.8) | 77 | 86.5, 77.5 to 92.3 |
| Bronchitis+COPD medication | 119 | 98 (82.4) | 44 | 44.4, 34.8 to 54.5 |
| Bronchitis only | 119 | 84 (70.6) | 26 | 29.5, 20.8 to 40.1 |
| Symptoms+spirometry | 119 | 83 (69.7) | 37 | 43.5, 33.2 to 54.4 |
| Symptoms only | 118 | 90 (75.6) | 11 | 12.2, 6.8 to 20.9 |