Eligible samples will be randomly divided into intervention and control groups. The intervention groups will be given codes A, B, C and the control group will receive code D. The study blocking is as follows: All block modes of these 4 groups are 24 numbers: ABCD, ABDC, ACDB, ACBD, ADBC, ADCB, BACD, BADC, BCAD, BCDA, BDAC, BDCA, CABD, CADB, CBAD, CBDA , CDAB, CDBA, DABC, DASB, DBCA, DBAC, DCAB, DCBA. These blocks will be placed in sealed envelopes inside a container. Then they will be drawn one by one, the first block to be removed will be selected as the first block. In fact, this will be repeated 28 times to complete the sample size. In this way, people enter the study and thus will be divided into groups.