Three statistical studies, all published between 2004 and 2008 but without referring to one another, assert a useful equivalence involving the hazard ratio, a parameter estimated for time to event data by the frequently used proportional hazards model. Stated generally, when the assumption of proportional hazards is justified, the hazard ratio is equivalent to the odds that a randomly chosen person from the group whose hazard is represented in the ratio's numerator will experience the event of interest before a randomly chosen person from the group represented by the ratio's denominator.

翻译：三项统计研究均在2004年至2008年期间公布,但没有相互参照,它们都主张危害比率是有用的等值,这是经常使用的比例危害模型对时间和事件数据的估计参数。 一般地说,在有理由假定相称危害时,危险比率相当于从该比率的分子中随机挑选的某一群体中其危害代表的人在随机选定该比率分母所代表的群体的人之前可能遇到的利害关系。