clinical safety should be evaluated according to the condition of adverse drug events obtained through patients 39 reports researcher 39 s observation or inquiry in a non induced way one hundred and seventy six patients were randomly assigned in groups there were 88 patients in xinxue tablet group and 88 patients in placebo group 155 patients completed the trial and all the visits in which 83 patients were in the xinxue tablet group and 72 patients were in placebo group 172 patients used the drug and experienced at least one safety evaluation and they were listed in safe population 171 patients used the drug and experienced at least one efficacy evaluation and they were listed in itt population the 155 patients that completed cases were listed in pp population itt was the major study population 2 1 1 changes of cd4 cell counting of two groups before and after treatment comparison between changes of cd4 cell counting before treatment 1 3 6 months after treatment see table 2 1 2 2 mean least square lsmeans and 95 confidence interval of the value between cd4 cell counting of the two groups 6 months after treatment it was demonstrated in the above results that after 6 months 39 treatment cd4 counting of the xinxue tablet group increased and cd4 counting of the placebo.