Randomization and allocation
RECRUITMENT
Men in both trials who completed the baseline survey and provided contact information were directed to contact a research assistant responsible for randomly allocating participants (1:1) into standard-of-care or HCV self-testing arms using a randomized block design. A separate randomization procedure was used for each CBO to generate 12 HCV self-testing/SOC randomized assignments for trial 1 and 12 assignments for trial 2. The block sizes must take the 1:1 allocation ratio into account, so for 1:1 randomization of two groups, the block sizes that can fit into 12 must be one of the even numbers 2, 4, or 6. A block size of 2 is not recommended as it is possible for the investigators to correctly guess the allocations within the small blocks and become prematurely unblinded. Thus, each of the 12 randomized assignments within each CBO was generated using two blocks of size 6 or three blocks of size 4 where the number of blocks (2 or 3) was randomly chosen based on a virtual coin flip. The final randomization schedule was generated by an independent statistician who was not involved in participant recruitment or analyses using SAS version 9.4 (SAS Institute, Cary, NC, USA).