很早以前人们就已经发现不同的社会背景条件下,疾病和健康状况往往是不同的。但是,人们对于造成这种差别的原因的认识,则是很有限的。多年来人们推测:可能是人的血统不同,或暴露于有害的环境条件下,或是接受医疗保健的不良影响等这些无疑是造成社会人群中不同患病率的某些因素。社会流行学 It has long been discovered that under different social background conditions, diseases and health conditions are often different. However, people’s understanding of the causes of such differences is limited. Over the years people have speculated that it may be that people of different ancestry, or exposure to harmful environmental conditions, or the adverse effects of receiving medical care are undoubtedly certain factors that cause different prevalence in the social population. Social epidemiology