Fourteen studies (8,239 participants) met the inclusion criteria.
The prevalence was 5% (95% CI: 4, 8) in the low clinical probability group, 17% (95% CI: 13, 23) in the moderate clinical probability group, and 53% (95% CI: 44, 61) in the high clinical probability group.
The sensitivity of D-dimer testing in the low probability group was 88% (95% CI: 81, 92) and the specificity was 72% (95% CI: 65,78). The corresponding values in the moderate probability group were 90% (95% CI: 80, 95) and 58% (95% CI: 49, 67), respectively, and in the high probability group, 92% (95% CI: 85, 96) and 45% (95% CI: 37, 52).
The LRs for a normal result among patients with low clinical suspicion were 0.10 (95% CI: 0.03, 0.37) with a highly sensitive D-dimer assay and 0.20 (95% CI: 0.12, 0.31) with a moderately sensitive D-dimer assay. For patients with moderate clinical suspicion the LRs were 0.05 (95% CI: 0.01, 0.21) and 0.23 (95% CI: 0.13, 0.39), respectively, and for patients with high clinical suspicion they were 0.07 (95% CI: 0.03, 0.18) and 0.15 (95% CI: 0.10, 0.38).