问题
多项选择题
病例对照研究在研究病因时主要缺点有()
A.统计处理复杂
B.难以得到符合要求的对照
C.回忆偏倚大
D.时间顺序有时不清
E.一次只能研究有限的几个因素
答案
参考答案:C, D
病例对照研究在研究病因时主要缺点有()
A.统计处理复杂
B.难以得到符合要求的对照
C.回忆偏倚大
D.时间顺序有时不清
E.一次只能研究有限的几个因素
参考答案:C, D
根据短文内容用框格内的适当形式填空。 | |
the 3____ . The doctor 4____ over Mrs.Brown for a few 5____ , then the doctor said, "I'm afraid you are too fat.""Too fat?"asked Mrs.Brown. The doctor said Mrs.Brown 6____ too much food and she didn't 7____ much exercise. Mrs.Brown 8____ the doctor what to do. The doctor said, "If you want to be 9____ and keep 10____, you have to eat less food." |