Assignment
Patients were randomly assigned by permuted block randomization (six blocks) to undergo either the EFTP interventional procedure or an endoscopic sham procedure, with a target allocation ratio of 1:1. Computer-generated randomization assignments were obtained before study enrollment by a statistician who was not part of the study. Individual patient assignments were prepared (N.K.) in sequentially numbered opaque sealed envelopes. A numbered envelope was drawn (A.M.) at the time of the procedure from a set of sealed envelopes containing the allocation. Patients were unaware of their group assignment. Patient blinding was lifted once 6 months’ follow-up was completed.