作者在智利挑选6～12周龄的婴儿随机分为3组,分别在每组婴儿的两臂各注射一针,3种接种方案为:第1组,一臂接种DTP/b型流感杆菌荚膜多糖-破伤风类毒素结合(HibPS-T)菌苗,另一臂注射安慰剂;第2 The authors selected infants from 6 to 12 weeks of age in Chile to divide into three groups randomly. One injection was given to each of the two arms of each infant. The three vaccination programs were: Group 1, one-arm vaccination of DTP / b influenza bacilli The membrane polysaccharide-tetanus toxoid-associated (HibPS-T) vaccine, the other arm was injected with placebo;