GRADE test accuracy evidence summary for VWF:GPIbR in patients with suspected VWD
| Sensitivity: 0.80-1.00 Specificity: 0.81-0.97 | Prevalences: 3%, 20%, 50% |
| Sensitivity: 0.80-1.00 Specificity: 0.81-0.97 | 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) | 4;404 | Cohort & case-control type studies | Serious‡ | Not serious | Not serious | Not serious | None | 24-30 | 160-200 | 400-500 | ⨁⨁⨁◯ MODERATE |
| False negatives (patients incorrectly classified as not having VWD) | 0-6 | 0-40 | 0-100 | ||||||||
| True negatives (patients without VWD) | 4;575 | Cohort & case-control type studies | Serious‡ | Not serious | Not serious | Not serious | None | 786-941 | 648-776 | 405-485 | ⨁⨁◯◯ LOW |
| False positives (patients incorrectly classified as having VWD) | 29-184 | 24-152 | 15-95 | ||||||||
| 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) | 4;404 | Cohort & case-control type studies | Serious‡ | Not serious | Not serious | Not serious | None | 24-30 | 160-200 | 400-500 | ⨁⨁⨁◯ MODERATE |
| False negatives (patients incorrectly classified as not having VWD) | 0-6 | 0-40 | 0-100 | ||||||||
| True negatives (patients without VWD) | 4;575 | Cohort & case-control type studies | Serious‡ | Not serious | Not serious | Not serious | None | 786-941 | 648-776 | 405-485 | ⨁⨁◯◯ LOW |
| False positives (patients incorrectly classified as having VWD) | 29-184 | 24-152 | 15-95 | ||||||||
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. Also, 3 of the 4 studies (Boender [2018],47 Vangenechten [2018],48 and Sagheer [2016])49 investigated test accuracy for classifying type 2 VWD patients (using a ratio of 0.6), not for diagnosing VWD.
Typically seen in patients investigated for VWD because of a personal history of abnormal laboratory test (eg, increased partial thromboplastin time).