Randomization and allocation concealment
BLIND
An independent researcher who was unaware of the representation of the codes assigned to groups produced the randomization code sequence in the WinPepi program (v. 11.65). Following the order generated, the numerical series was preserved in opaque envelopes consecutively numbered from 1 to 60. We kept it secret and kept out of the reach of the participants and evaluators who were blind to the allocation of the sequence of codes until the study’s conclusion.