Table 3. Estimates of Probability of Disease Before Testing and After Positive or Negative Test Results for 5 Testing Questions .
| Clinical scenario | Scientific evidence range, % | Median (IQR) | ||
|---|---|---|---|---|
| Resident physician estimate, % (n = 290) | Attending physician estimate, % (n = 202) | Nurse practitioner or physician assistant estimate, % (n = 61) | ||
| Pneumonia | ||||
| Pretest probability | 25-42 | 80 (75-90) | 85 (80-90) | 80 (70-90) |
| After positive test result | 46-65 | 95 (90-99) | 95 (95-100) | 95 (90-100) |
| After negative test result | 10-19 | 60 (40-80) | 50 (20-80) | 50 (20-50) |
| Breast cancer | ||||
| Pretest probability | 0.2-0.3 | 5 (1-10) | 2 (1-10) | 10 (5-20) |
| After positive test result | 3-9 | 60 (35-75) | 50 (20-80) | 60 (50-80) |
| After negative test result | <0.05 | 5 (1-10) | 1 (1-10) | 10 (2-20) |
| Cardiac ischemia | ||||
| Pretest probability | 1-4.4 | 10 (5-20) | 5 (3-10) | 15 (6.25-30) |
| After positive test result | 2-11 | 75 (50-90) | 60 (25-80) | 90 (60-95) |
| After negative test result | 0.43-2.5 | 5 (1-10) | 5 (1-10) | 10 (5-20) |
| Urinary tract infection | ||||
| Pretest probability | 0-1 | 25 (10-60) | 20 (5-50) | 30 (10-50) |
| After positive test result | 0-8.3 | 77.5 (25-95) | 90 (40-98) | 90 (75-100) |
| After negative test result | 0-0.11 | 5 (0.1-20) | 5 (0-10) | 5 (0-10) |
| Hypothetical testing situation | ||||
| After positive test result | 2 | 95 (95-95) | 95 (80-100) | 95 (95-100) |
| After negative test result | 0 | 2 (0-10) | 5 (0-5) | 5 (5-75) |
Abbreviation: IQR, interquartile range.