In this study, block randomization was used to ensure equilibrium of participants in two groups (mild Alzheimer's block or moderate Alzheimer's block). For this purpose, four-membered blocks consisting of all four possible combinations were defined as having two A members (intervention group) and two B members (control group), and at the time of randomization, a block was randomly selected and the samples assigned to the intervention or control group based on the results. The six possible four combinations are:
AABB, ABAB, ABBA, BAAB, BABA, BBAA
One envelope was provided for each block, containing four cards, two cards marked A and two cards B. The order of the cards in each envelope was in accordance with one of the above patterns and we had a total of six envelopes (numbered from one to six). At the time of random allocation, one of the envelopes was randomly selected, and as a result, four patients entered the study and their assignment was identified. when the envelope was identified, all four cards were not pulled out together, but with each patient, one card (in the envelope, respectively) was removed and discarded. After inserting four samples into two groups, the cards were placed in the same order at the envelope, and the envelope was returned to its original location.