GWD 21-4

michellemove

Which of the following most logically completes the passage?

Appendicitis (inflammation of the appendix) is potentially fatal; consequently, patients with symptoms strongly suggesting appendicitis almost have their appendix removed. The appropriate surgery is low-risk but performed unnecessarily in about 20 percent of all cases. A newly developed internal scan for appendicitis is highly accurate, producing two misdiagnoses for every 98 correct diagnoses. Clearly, using this test, doctors can largely avoid unnecessary removals of the appendix without, however, performing any fewer necessary ones than before, since .

A. the patients who are correctly diagnosed with this test as not having appendicitis invariably have medical conditions that are much less serious than appendicitis

B. the misdiagnoses produced by this test are always instances of attributing appendicitis to someone who does not, in fact, have it

C. all of the patients who are diagnosed with this test as having appendicitis do, in fact, have appendicitis

D. every patient who is diagnosed with this test as having appendicitis has more than one of the symptoms generally associated with appendicitis (B)

E. the only patients who are misdiagnosed using this test are patients who lack one or more of the symptoms that are generally associated with appendicitis

b in fact 修饰的可真不清楚啊

对文章最后一句心存疑惑，谁给翻译下？

LHL888

Clearly, using this test, doctors can largely avoid unnecessary removals of the appendix without, however, performing any fewer necessary ones than before, since .

使用现在这个test 医生可以大幅避免不必要的移除 而不减少必要的移除

简言之 减少没病却被开刀的同时 有病却没检查出的不会应而增加

这是因为....这个测试的误诊只会出现没病却诊断有病

wretdgdh

本题关键是without, however, performing any fewer necessary ones than before。

因为新方法有2%的误诊，要达到进行的必要的手术（即病人确实得了阑尾炎）不比原来有任何减少（原来的方法可以认为是指进行了不必要的手术，得病的都做了手术）。那么，新的方法必须保证，误诊的2%是没有阑尾炎而被判为有阑尾炎的。否则，新方法就有可能performing any fewer necessary ones than before了。