Treatment guided by cerebral oximetry monitoring in extremely preterm infants: a Bayesian analysis of the SafeBoosC-III randomised clinical trial

Purpose: The SafeBoosC-III trial compared treatment guided by cerebral oximetry monitoring for the first 72 h after birth with usual care in 1601 extremely preterm infants. Incidence of death or severe brain injury at 36 weeks of postmenstrual age did not differ between the cerebral oximetry and usual care group (relative risk with cerebral oximetry, 1.03; 95% CI 0.90 to 1.18). To assess the probability of clinically important benefit or harm, we conducted secondary analyses in a Bayesian framework. Methods: Primary analyses used a weakly informative prior assuming a wide range of effects, to assess the probability that treatment guided by cerebral oximetry monitoring carried an a priori defined clinically important benefit or harm (a relative risk below 0.90 or above 1.10) or any benefit or harm (a relative risk differing from 1.0) for death or severe brain injury. Secondary analyses used an evidence-based prior derived from relevant prior trials. Results: Posterior probabilities of clinically important benefit or harm were 1.5% and 19.2%, respectively. Posterior probabilities of any benefit or harm were 28.7% and 71.3%, respectively. Probabilities derived from secondary analyses using evidence-based priors were consistent with those from the primary analysis. Conclusion: Treatment guided by cerebral oximetry monitoring during the first 72 h after birth in extremely preterm infants resulted in posterior probabilities of 1.5% for a clinically important benefit and 19.2% for a clinically important harm with respect to the incidence of death or severe brain injury at 36 weeks of postmenstrual age. Trial registration: ClinicalTrials.gov NCT03770741. Registered on 12 July 2018.