Patients are assigned in a 1:1 ratio to one of the experimental (B) and control (A) groups using a computer-generated random number sequence using a block of four. Given the block size of four, there will be a total of six blocks as AABB, ABAB, ABBA, BBAA, BABA, BAAB. After the blocks are numbered, each block is used for four patients. In this case, if block number one is randomly selected, the first patient will be in group A, the second patient in group A, the third patient in group B, and the fourth patient in group B. For the fifth patient, one of the blocks is randomly selected again, and the fifth to eighth patients will be assigned to group A or B, respectively. This method will continue until the desired sample size is reached.