问题 问答题 简答题

病例对照研究具有什么特点?

答案

参考答案:

病例对照研究在探讨、检验暴露与效应之间的关系时,应用社会学、统计学、逻辑学和医学等的相关理论和方法,从不同角度进行论证、推导和分析,使病例对照研究相对于描述性和实验性研究来说具有独特的方法学色彩,因此,在流行病学方法学上分属分析性研究。病例对照研究在分析暴露与效应的关系时,通过设立专门的比较组,使暴露与效应之间的关系获得“反面”的证据。病例对照研究通过调查“现在”的病例“过去”的暴露史,即研究方向由果及因,因而具有回顾性的研究性质。正是由于“回顾性”,病例对照研究则难以避免各种偏倚对研究的影响,因此,它在病因研究中的作用和地位被限定在“探索并检验病因假设”,而不是“验证病因假设”上。

此外,病例对照研究还具有适合于对罕见病的研究和省时省力的优势。

单项选择题
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John and Bobby joined a wholesale company together just after graduation from college the same year. Both worked very hard. After several years, however, the boss promoted (提升) Bobby to the position of manager but John remained an ordinary worker. John couldn't understand it anymore, gave his resignation(辞呈) to the boss and complained that the boss didn't value hardworking workers, but only promoted those who flattered (奉承)him.

The boss knew John worked very hard for the years. He thought for a moment and said, "Thank you for your criticism(批评), but I have a request. I hope you'll do one more thing for our company before you leave. Perhaps you'll change your mind and take back your resignation."

John agreed. The boss asked him to go and find out anyone selling watermelon on the market. John went and returned soon. He said he had found out a man selling watermelon. The boss asked how much per kg? John shook his head and went back to the market to ask and returned to tell the boss$1.2 per kg.

Boss told John to wait a second, and he called Bobby to come to his office. He asked Bobby to go and find anyone selling watermelon on the market. Bobby went, returned and said,"Boss, only one person selling watermelon. $1.2 per kg, and $ 10 for 10 kg. He has 340 melons in all, 58 of which are on the table. Every melon weights about 2kg. Bought from the South two days ago, they're fresh and red, good quality."

John was very impressed and realized the difference between himself and Bobby. He decided not to resign but to learn from Bobby.

My dear friends, chances exist in the daily details. For the same matter, a more successful person sees more and farther so that he can find out an opportunity and catch it to achieve his aim.

小题1:According to the first paragraph, John thought that _____.

A.Bobby was lazy though he was clever

B.it was unfair that the boss just promoted Bobby

C.Bobby wasn't fit to be a manager

D.the boss disliked hardworking workers小题2:The boss told John and Bobby to go to find anyone selling watermelon on the market in order to __.

A.show watermelons were in great need on the market

B.test their abilities to make market research

C.make John find out the differences between them two

D.convince John of Bobby's ability to do business小题3:It is known from the text that John was hardworking but _____.

A.a little stupid

B.a little rude

C.not good at learning

D.not thoughtful小题4:The story shows such an opinion that _____.

A.a successful person observes and thinks more

B.a successful person is curious and eager to learn

C.the main key to success is to know what you want

D.one's success sometimes is not related to his hard work