Introduction
infection, bacterial infection, ’ endothelial dysfunction
PCT, BACTERIAL INFECTION, INFECTION, SECONDARY, HAND PRESENTATION, ENDOTHELIAL DYSFUNCTION
Most hospitals in the UK National Health Service (NHS) use a blood test called C-reactive protein (CRP) to monitor response to infection, but it is not specific for bacterial infection and shows a delayed response. Procalcitonin (PCT) is a blood test which is specific for bacterial infection and responds more quickly than CRP [BATCH (biomarker-guided duration of antibiotic treatment in children hospitalised with confirmed or suspected bacterial infection) is a randomised controlled trial to compare PCT-guided management of severe bacterial infection in children with current management [PRECISE (MR-proADM [mid-regional pro-adrenomedullin] and ImmunoXpert evaluation of PCT-guided antibiotic duration in children with infection for stratification of effectiveness) is a mechanistic sub-study embedded into the BATCH trial. The aim of this sub-study is to determine if the effectiveness of the PCT-guided algorithm in reducing IV antibiotic duration varies depending on patients’ endothelial dysfunction (as measured by MR-proADM) and host immune response (as quantified by ImmunoXpert score).This paper describes the statistical analysis plan (SAP) for the BATCH trial and PRECISE sub-study in advance of trial completion, including statistical principles, procedures for the analysis and presentation of primary and secondary trial outcomes, and pre-specified subgroup analyses.