C Section
* Standardised rates: The stabilised & adjusted mortality rate for each organisation is calculated by multiplying the appropriate ’comparator’ mortality rate by an organisation-specific standardised mortality ratio calculated from the data. For the Trusts and Health Boards of birth the comparator mortality rate is the overall rate for Trusts and Health Boards in the same comparator group. The SMR is estimated using a multilevel logistic regression model. A multilevel model is used as it can accommodate the hierarchical structure of the data through the random term; that is, births clustered within organisations. These models also allow the calculation of stabilised (also known as 'shrunken' or 'smoothed') estimates of the organisation-specific terms, which reduce the likelihood of organisations being falsely identified as outliers by chance alone. For more info see page 6 - https://www.npeu.ox.ac.uk/assets/downloads/mbrrace-uk/reports/perinatal-surveillance-report-2020/MBRRACE-UK_Perinatal_Surveillance_Report_Technical_document.pdf