In this study, four permuted blocks consisted of the English letters A,B,C,D. The letters B, and A would be denoted the intervention group, and C, and D would be denoted the control group. The blocks are selected randomly and blindfolded. Each block is then deleted, and the next random block is selected. With each block, the entrance order to the intervention group or the control group is determined. Assumingly; block D, A, C, and B would be meant that the second, and fourth subjects are entered in the intervention group and the first, and third subjects are entered in the control group. The patients were divided into two equal groups, with 20 patients in the intervention group and 20 patients in the control group.