Acknowledgement
PJH and PJK are chief investigators of the RESCUEicp study. IT, AGK, EAC and MC are members of the RESCUEicp central study team. DKM and JDP are members of the RESCUEicp steering committee.
Declaration of interest: The RESCUEicp study is funded by a Medical Research Council/National Institute of Health Research Clinical Trials grant.