GRADE test accuracy evidence summary for BAT when used as a screening test for VWD
| . | Sensitivity . | 0.75 (95% CI, 0.66-0.83) . | . | Prevalences . | 3% . | 20% . | 50% . | . | |||
|---|---|---|---|---|---|---|---|---|---|---|---|
| . | Specificity . | 0.54 (95% CI, 0.29-0.77) . | . | . | . | ||||||
| . | Factors that may decrease certainty of evidence . | Effect per 1000 patients tested . | . | ||||||||
| Outcome . | No. of studies (No. of patients) . | Study design . | Risk of bias . | Indirectness . | Inconsistency . | Imprecision . | Publication bias . | Pretest probability of 3%* . | Pretest probability of 20%† . | Pretest probability of 50%‡ . | Test accuracy CoE . |
| True positives (patients with suspected patients) | 7 studies, 112 patients | Cross-sectional (cohort type accuracy study) | Not serious | Not serious | Not serious | Not serious | None | 23 (20-25) | 150 (132-165) | 376 (331-413) | ⨁⨁⨁⨁ HIGH |
| False negatives (patients incorrectly classified as not having suspected patients) | 7 (5-10) | 50 (35-68) | 124 (87-169) | ||||||||
| True negatives (patients without suspected patients) | 7 studies, 863 patients | Cross-sectional (cohort type accuracy study) | Not serious | Not serious | Serious§ | Not serious | None | 523 (284-744) | 431 (234-614) | 270 (147-384) | ⨁⨁⨁◯ MODERATE |
| False positives (patients incorrectly classified as having suspected patients) | 447 (226-686) | 369 (186-566) | 230 (116-353) | ||||||||
| . | Sensitivity . | 0.75 (95% CI, 0.66-0.83) . | . | Prevalences . | 3% . | 20% . | 50% . | . | |||
|---|---|---|---|---|---|---|---|---|---|---|---|
| . | Specificity . | 0.54 (95% CI, 0.29-0.77) . | . | . | . | ||||||
| . | Factors that may decrease certainty of evidence . | Effect per 1000 patients tested . | . | ||||||||
| Outcome . | No. of studies (No. of patients) . | Study design . | Risk of bias . | Indirectness . | Inconsistency . | Imprecision . | Publication bias . | Pretest probability of 3%* . | Pretest probability of 20%† . | Pretest probability of 50%‡ . | Test accuracy CoE . |
| True positives (patients with suspected patients) | 7 studies, 112 patients | Cross-sectional (cohort type accuracy study) | Not serious | Not serious | Not serious | Not serious | None | 23 (20-25) | 150 (132-165) | 376 (331-413) | ⨁⨁⨁⨁ HIGH |
| False negatives (patients incorrectly classified as not having suspected patients) | 7 (5-10) | 50 (35-68) | 124 (87-169) | ||||||||
| True negatives (patients without suspected patients) | 7 studies, 863 patients | Cross-sectional (cohort type accuracy study) | Not serious | Not serious | Serious§ | Not serious | None | 523 (284-744) | 431 (234-614) | 270 (147-384) | ⨁⨁⨁◯ MODERATE |
| False positives (patients incorrectly classified as having suspected patients) | 447 (226-686) | 369 (186-566) | 230 (116-353) | ||||||||
CoE, certainty of evidence.
Typically seen in patients investigated for VWD because of a personal history of abnormal laboratory test (eg, increased APTT).
Typically seen in patients investigated for VWD because of a personal history of bleeding symptoms (eg, mucocutaneous bleeding).
Typically seen in in patients investigated for VWD as a first-degree relative for a patient with VWD.
The point estimates of specificity are not homogenous, which was not explained by a priori determined analysis (eg, based on difference in risk of bias of the studies), and can be due to differences in the setting and disease prevalence. The majority of included studies were judged to be low risk of bias for test and reference standard interpretation. Although there was unclear reporting regarding flow and timing in some studies, the certainty of evidence was generally not downgraded for risk of bias. The patient selection risk of bias was low in 7 cohort studies and high in 6 case control studies that were not included to calculate the pooled estimate.