Randomization, washout, and blinding
orthostasis
Subjects were randomized at a 1:1 ratio to one of two verticalization groups: the
sitting position followed by passive orthostasis group or the passive
orthostasis followed by the sitting position group. Participants were randomized
on the same day they were deemed to be suited to participate in the study.
Randomization was performed using blocks of different sizes and stratified by
center. Allocation sequencing and concealment were ensured through the use of a
centralized web-based randomization platform (REDCap, Vanderbilt University,
Nashville, TN, USA).