“需治疗人数”(number needed to treat,NNT)被定义为绝对危险度减少值的倒数,它是指为预防1例不良事件发生,临床医师在一段时间内应用某一疗法需治疗的患者数。NNT及其扩展指标NNTus(有效且无副作用)和NNHUF(不仅无效且发生副作用)具体直观,贴近医生和患者的实际要求,可对药物疗效及其不良反应进行综合评价,还可利用它们方便地进行成本-效益分析,是评价药物不良反应的较好指标。 Number needed to treat (NNT) is defined as the inverse of the absolute risk reduction and refers to the number of patients treated by a clinician for a given period of time to prevent the occurrence of an adverse event . NNTs and its extensions NNTus (effective and without side effects) and NNHUF (not only ineffective and side-effects) are specific and intuitive, close to the actual requirements of doctors and patients, can be evaluated comprehensively on the efficacy and side effects of the drugs, and can be conveniently used Cost-benefit analysis is a good indicator of adverse drug reactions.