From: Antenatal screening for Group B Streptococcus: A diagnostic cohort study
LVS | PAS | Either | LVS | PAS | Either | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
32 Weeks (n = 600) | 36 Weeks (n = 600) | (n= 699) | ||||||||||||
Estimate + 95% CI | Estimate + 95% CI | Estimate + 95% CI | Estimate + 95% CI | Estimate + 95% CI | Estimate + 95% CI | Estimate + 95% CI | ||||||||
Sensitivity | 63 | 54–71 | 70 | 61–77 | 72 | 63–79 | 73 | 65–81 | 76 | 67–83 | 81 | 73–87 | 19 | 13–26 |
Specificity | 94 | 92–96 | 94 | 91–96 | 93 | 90–95 | 95 | 93–97 | 94 | 91–96 | 93 | 90–95 | 83 | 79–86 |
PPV* | 77 | 68–84 | 76 | 68–84 | 75 | 66–82 | 82 | 74–88 | 78 | 70–85 | 77 | 69–84 | 25 | 18–34 |
NPV | 90 | 87–92 | 91 | 89–94 | 92 | 89–94 | 92 | 90–95 | 93 | 90–95 | 94 | 92–96 | 77 | 73–80 |
Likelihood ratio (+ve) | 11.3 | 7.6–16.7 | 11.2 | 7.7–16.2 | 10.1 | 7.2–14.3 | 15.5 | 10.2-23.6 | 12.1 | 8.4-17.5 | 11.7 | 8.3-16.6 | 1.10 | 0.76-1.59 |
Likelihood ratio (-ve) | 0.39 | 0.31–0.49 | 0.32 | 0.25–0.42 | 0.30 | 0.23–0.40 | 0.28 | 0.21–0.37 | 0.26 | 0.19–0.35 | 0.21 | 0.15–0.29 | 0.98 | 0.90–1.06 |
Diagnostic Odds Ratio | 28.7 | 16.4–50.6 | 34.5 | 19.8–60.4 | 33.4 | 19.4–57.9 | 55.4 | 30.1–103 | 46.5 | 26.1–83.1 | 56.7 | 31.4–103 | 1.12 | 0.69–1.79 |