| Parameter |
Base-Case Estimate (Range) |
Reference |
|
| Population risks, % |
|
|
| Prevalence of rectovaginal colonization with GBS |
22.8 (18.2–27.4) |
6, 19, 22, 35–38 |
| Prevalence of vaginal colonization with GBS |
14.7 (11.8–17.6) |
19, 22, 35, 36, 39–42 |
| Probability of receiving adequate prenatal care |
95 (70–100) |
50 |
| Probability of having risk factors during labor (at term) |
7.56 (6.05–9.07) |
19, 22, 43–45 |
| Test characteristics, % |
|
|
| PCR sensitivity |
100 (80–100) |
28 |
| PCR specificity |
98.9 (80–100) |
28 |
| 35- to 37-wk culture sensitivity |
90.8 |
19, 22, 43 |
| 35- to 37-wk culture specificity |
88.9 |
19, 22, 43 |
| Infection rates, % |
|
|
| Probability of infant infection given maternal GBS colonization (in the genital tract, at time of labor) |
1.47 (1.18–1.76) |
5, 19, 22, 46, 47 |
| Probability of infant infection given no maternal GBS colonization (in the genital tract, at time of labor) |
0.0017 (0.0013–0.002) |
5, 19, 22, 46, 47 |
| Probability of infant infection given maternal risk factors |
1.4 (1.12–1.68) |
19, 22, 43 |
| Probability of infant infection given no maternal risk factors |
0.12 (0.096–0.14) |
19, 22, 43 |
| Decrease in infant infection rate after maternal prophylaxis |
80.2 (70–86) |
19, 48, 49 |
| Outcomes, % |
|
|
| Probability of infant death after infection |
1 (0–5) |
1, 4, 20 |
| Probability of infant disability after infection |
1.6 (0–10) |
1, 20 |
| Probability of infant recovery and wellness after infection |
97.4 (90–100) |
1, 20 |
| Costs / benefits, $* |
|
|
| PCR test |
26 (16–54) |
See "Methods" |
| 35- to 37-wk culture |
21 |
See "Methods" |
| Maternal antibiotic prophylaxis |
63 (30–115) |
See "Methods" 16–18, 20 |
| In-hospital care of well (not infected) infant |
1100 (500–1500) |
See "Methods" |
| NICU care of GBS-infected infant |
30 100 (12 000–128 000) |
See "Methods" |
| Discounted lifetime health care costs for a healthy infant |
33 300 (16 300–50 000) |
See "Methods" 54–56 |
| Discounted lifetime health care costs for a disabled infant |
294 000 (60 500–500 000) |
See "Methods" 52 |
| Discounted expected lifetime earnings for a healthy infant |
411 200 (290 000–550 000) |
See "Methods" 53, 54, 56 |
| Discount rate, % |
3 |
|
|