2.6. Randomization, allocation concealment, and blinding
The random allocation list was generated by an independent research assistant (T-J) with no other role in this trial using SPSS software (IBM Corp., Armonk, NY, USA), and was prepared and concealed in 70 opaque, sealed, and sequentially numbered envelopes. The acupuncturist (H-X) opened the sealed envelopes once participants were at the first treatment session. If two or more participants received interventions on the same day, they were scheduled to come to the hospital at different times to avoid communication and interaction. Group allocation was kept confidential from participants, outcome assessors (FY-Z and YL-H), and the statistician (QQ-F). Only the independent research assistant (T-J) and the acupuncturist (H-X) knew the treatment allocation. The unblinding process was only executed after all the statistical analyses were completed.