GRADE test accuracy evidence summary for VWF:GPIbM in patients with suspected VWD
| Sensitivity: 0.62-0.82 Specificity: 0.90-0.97 | Prevalences: 3%, 20%, 50% |
| Sensitivity: 0.62-0.82 Specificity: 0.90-0.97 | Prevalences: 3%, 20%, 50% |
| Outcome . | Studies (n); patients (n) . | Study design . | Factors that may decrease certainty of evidence . | Effect per 1000 patients tested . | Test accuracy CoE . | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Risk of bias . | Indirectness . | Inconsistency . | Imprecision . | Publication bias . | Pretest probability of 3%* . | Pretest probability of 20%† . | Pretest probability of 50%‡ . | ||||
| True positives (patients with VWD) | 2;249 | Cohort & case-control type studies | Serious§ | Not serious | Not serious | Not serious | None | 19-25 | 124-164 | 310-410 | ⨁⨁◯◯ LOW |
| False negatives (patients incorrectly classified as not having VWD) | 5-11 | 36-76 | 90-190 | ||||||||
| True negatives (patients without VWD) | 2;513 | Cohort & case-control type studies | Serious§ | Not serious | Not serious | Not serious | None | 873-941 | 720-776 | 450-485 | ⨁⨁◯◯ LOW |
| False positives (patients incorrectly classified as having VWD) | 29-97 | 24-80 | 15-50 | ||||||||
| Outcome . | Studies (n); patients (n) . | Study design . | Factors that may decrease certainty of evidence . | Effect per 1000 patients tested . | Test accuracy CoE . | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Risk of bias . | Indirectness . | Inconsistency . | Imprecision . | Publication bias . | Pretest probability of 3%* . | Pretest probability of 20%† . | Pretest probability of 50%‡ . | ||||
| True positives (patients with VWD) | 2;249 | Cohort & case-control type studies | Serious§ | Not serious | Not serious | Not serious | None | 19-25 | 124-164 | 310-410 | ⨁⨁◯◯ LOW |
| False negatives (patients incorrectly classified as not having VWD) | 5-11 | 36-76 | 90-190 | ||||||||
| True negatives (patients without VWD) | 2;513 | Cohort & case-control type studies | Serious§ | Not serious | Not serious | Not serious | None | 873-941 | 720-776 | 450-485 | ⨁⨁◯◯ LOW |
| False positives (patients incorrectly classified as having VWD) | 29-97 | 24-80 | 15-50 | ||||||||
Typically seen in patients investigated for VWD because of a personal history of abnormal laboratory test (eg, increased PTT).
Typically seen in patients investigated for VWD because of a personal history of bleeding symptoms (eg, mucocutaneous bleeding) (Quiroga, 2007).46
Typically seen in patients investigated for VWD as a first-degree relative of a patient with VWD.
Serious patient selection risk of bias due to case-control design. Diagnostic test accuracy results for classifying type 2 VWD patients (using a 0.6 ratio), not for diagnosing VWD.