Randomization
A computer-generated block randomization was designed to provide each
site with a blinded randomized sequence assigning the PEEP level during
HCPAP therapy. An initial sequence of 50 patients was sent to the study
coordinator at each site, with an equal number of patients in each group
at all sites. The subsequent planned blocks were not sent after study
interruption. After patients were randomly assigned to the study groups
and achievement of informed consent, the PEEP level enrollment group was
revealed, and it was open to all caregivers due to the impossibility of
blinding it.