请教一道04.05逻辑机井--->beautywawa转移

PlanetLonely

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 always 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 having 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

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 (2004.04.26)

answer : b?

why C is not correct?

C和B说的误诊情况是一样的，只不过B直接说，C说相反的情况不可能发生误诊

thx

[此贴子已经被作者于2005-5-8 16:04:23编辑过]

IceOnMe

我也觉得是C

但BC不一样吧

B说的是这种TEST的误诊是把没有的说成有的 还是会误割,虽然只有2个,只能说明大大减少了误割情况,但不是without performing any fewer necessory ones 也就是说只影响了"割了不该割的" 而对"该割的不割"没有影响

C说的是只要被TEST确诊有的,就肯定有  ----那100个CASE里的那2个CASE, TEST肯定是把有的说成了没有, 就会出现"该割的不割"这种情况,和without performing any fewer necessory ones 是符合的

好搞啊这题, 实战的时候要1分钟做出来大大的困难, 至少5分钟

[此贴子已经被作者于2005-5-8 16:43:06编辑过]

ring_cheng

这道题我以前也问过的，MINDFREE 大牛给了解释，请看：

http://forum.chasedream.com/dispbbs.asp?BoardID=24&ID=102618

IceOnMe

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

很明显,用了这种TEST, 医生可以大大避免不必要的割除同时没有任何的"该割不割"

我居然理解成 避免不必要割除的同时 有"该割不割"的情况

不知道自己是怎么想的~ THX~  这个就叫逻辑混乱吧~