Main contribution
Cambridge statistician and former RSS president Sir David Spiegelhalter gave a formal witness statement to the Thirlwall Inquiry, dated 15 January 2025, analysing whether existing statistical-monitoring systems would have flagged the 2015-16 rise in neonatal deaths at the Countess of Chester Hospital. He examined the unit's data through the MBRRACE-UK and CQC outlier-detection frameworks and carried out his own statistical calculation using the unit's historical death counts.