Cost-effectiveness of rapid tests and other existing strategies for screening and management of early-onset group B streptococcus during labour

Objective: To determine the cost-effectiveness of alternative screening and prevention strategies, including rapid intrapartum testing, for prevention of early-onset neonatal group B streptococcus (GBS) infection in the UK.

Design: A decision model was developed to investigate the cost-effectiveness of screening and prevention strategies for GBS. A strategy of doing nothing was also considered. Deterministic and probabilistic sensitivity analyses were carried out.

Setting: Two large UK based obstetric units.

Participants: Test accuracy data were obtained from a primary study of rapid tests at the onset of labour and risk factors from 1400 women.

Main outcome measures: Incremental health sector costs per case of early-onset GBS death avoided.

Results: Compared with a strategy of do nothing, the incremental cost-effectiveness ratio was £32,000 per Early-Onset GBS Disease avoided and £427,000 per Early-Onset GBS Death avoided for the strategy of providing routine intrapartum antibiotic prophylaxis to all women without prior screening; Based on their current sensitivity, specificity and cost, screening using rapid tests was dominated by other more cost-effective strategies.

Conclusions: The most cost-effective strategy was shown to be the provision of routine intrapartum antibiotic prophylaxis to all women without prior screening but, given broader concerns relating to antibiotic use, this is unlikely to be acceptable. In its absence, intrapartum antibiotic prophylaxis directed by screening with enriched culture becomes cost-effective. The current strategy of risk-factor-based screening is not cost-effective compared with screening based on culture.