Comparing the Validity of Studies Using B-Type Natriuretic Peptide (BNP) to Diagnose Heart Failure.
| 1. Was there an independent, blind comparison with a reference standard of diagnosis? | |
| Cowie et al, 1995–199613 | May be assumed while blindness was not explicitly stated |
| Dao et al, 199911 | Yes |
| Maisel et al, 1999–200012 | Yes |
| Morrison et al, 1999–200015 | Yes |
| 2. Was the diagnostic test (BNP level) evaluated in a appropriate spectrum of patients (ie, NYHA class I–IV)? | |
| Cowie et al, 1995–199613 | Yes |
| Dao et al, 199911 | Yes |
| Maisel et al, 1999–200012 | Yes |
| Morrison et al, 1999–200015 | Yes |
| 3. Was the reference standard applied (ie, echocardiogram) regardless of the diagnostic test result? | |
| Cowie et al, 1995–199613 | Yes |
| Dao et al, 199911 | Yes |
| Maisel et al, 1999–200012 | Yes |
| Morrison et al, 1999–200015 | Yes |
| 4. Was the test validated in a second independent group of patients? | |
| Cowie et al, 1995–199613 | No |
| Dao et al, 199911 | No |
| Maisel et al, 1999–200012 | Yes* |
| Morrison et al, 1999–200015 | No |
Adapted from Evidence-Based Medicine: How to Practice and Teach EBM, by Sacket DL et al, 2nd edition; Churchill Livingston, 2000.
* The study by Dao et al may be considered as a second group by some authors.