risk factor

risk-factor的词性：
n.（名词）

1. A factor that increases one's chances of contracting a particular disease:
致病因素：增加某人得某种特殊疾病机率的因素：

“The report emphasizes that interaction of many risk factors is responsible for coronary heart disease in an individual”(Science News)
“报告强调指出：许多致病因素的相互反应是个人患冠状动脉心脏病的原因”(科学新闻)