Most studies could not quantify diseasefrequency in the general population as they are hospital-based and confounded by variations in threshold and the rate of hospitalization.
多数研究不能把一般人群当中的发病频率给予定量是因为它们是基于医院的并且被混杂在住院率的变化之中。
2
Malnutrition will increase, as will the number of deaths from diarrhoeal disease. More storms and floods will cause more deaths and injuries, and cholera outbreaks will occur with greater frequency.
Asthma is a chronic disease characterized by recurrent attacks of breathlessness and wheezing, which vary in severity and frequency from person to person.