Cost-Effectiveness of Universal Prophylaxis in Pregnancy with Prior Group B Streptococci Colonization

Table 1

Probability estimates used in the decision analysis.

Variable	Baseline estimate	Range for sensitivity analysis	References	Level of evidence*
Probability of being colonized with GBS in a subsequent pregnancy
	0.41	0.38–0.44	[3, 4]	II
Probability of early onset neonatal GBS sepsis if mother colonized and treated
	0.001	0–0.011	[12–17]	I
Probability of early onset neonatal GBS sepsis if mother colonized and not treated
	0.016	0.011–0.066	[8, 13–17]	I and II
Probability of early onset neonatal GBS sepsis if mother not colonized and given no treatment
	0.0002	0–0.0004	[8, 18]	II
Probability of early onset neonatal GBS sepsis if mother not colonized and given treatment
	0.00001	0–0.0004	See methods
Probability of not receiving planned antibiotic prophylaxis
	0.08	0.05–.11	[11, 19]	II
Probability of maternal anaphylaxis to penicillin
Penicillin	0.000205	0.00001–0.0004	[9, 20]	II and III
Cephalosporin	0.000215	.000015–0.0004	[20, 21]	II and III
Clindamycin	0.00007	0.000003–0.00013	See methods
Erythromycin	0.00007	0.000003–0.00013	See methods
Vancomycin	0.0002	0.00001–0.0004	[21]	III
Probability of maternal death from antibiotic anaphylaxis
	0.0000175	0.000015–0.00002	[9]	III
Probability of individual reporting an allergy to penicillin at high risk of anaphylaxis colonized
with GBS and having susceptibility testing done
	0.56	0.11–1	[11]	II
Culture positive gravidas receiving ≥4 hours intrapartum antibiotics
	0.55	0.53–0.65	[6, 7, 22]	II and III
Probability of a newborn limited diagnostic workup born to mothers colonized with GBS
who received <4 hours antibiotics before delivery
	0.52	0.04–1	[1, 6, 23]	II and III
Probability of obtaining a newborn CBC in neonates born to mothers negative for
GBS colonization
	0.07	0–0.14	[6, 23]	II

GBS: group B streptococci; CBC: complete blood count.
*US Preventive Services Task Force (10). Level I is the best evidence, and III is the worst evidence.