[問題]GWD21-4

[coulomb]

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

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

答案給B我選C
最後一句說：新的測試使得醫師可以在 需要的手術次數不減少的情況下 避免動多餘的手術
那這樣的話C為什麼不行呢？我看不出C跟B有什麼不一樣耶
不都是說測試結果很準確 所以不會開一些不必要的刀嗎？

[維尼]

c選項是 驗出有的都是對的 也就是不會造成測驗有但實際沒有 但不保證驗出沒有的實際上沒有
b選項是說 出錯都錯在實際沒有的 換句話說 實際有的都會被驗出來
所以b選項才是可以不減少要執行的手術

[coulomb]

喔～～原來如此～～
感謝維尼大大!!

[gaspper]

我還是不太懂... 最後一句話：
Clearly, using this test, doctors can largely avoid unnecessary removals of the appendix without, however, performing any fewer necessary ones than before,

意思是不是說，醫生能在避免不必要之闌尾手術時，"還能避免施行更少之必要手術"→也就是使用 NEW TEST 不但能避免不必要的手術，還能不減少必要的手術。

B 的 this test 指的是新 test, 那意思就是 new test "出錯都錯在實際沒有的". 既然new test 會把沒有的看成有的，為什麼會是正確答案呢 ? 我對句意的理解有錯嗎?

[gerjyh]

Clearly, using this test, doctors can largely avoid unnecessary removals of the appendix without, however, performing any fewer necessary ones than before,since
我想你的理解沒有錯
只是你漏看了largely avoid 就是說new test只能"大量"避免不必要的手術 我們要的答案是不會減少必要手術的選項
答案b說的錯誤都發生在實際沒有的 把沒有的看成有的並不會減少必要的手術

[Chris1]

請問一下一個問題,
原文中的這句話"The appropriate surgery is low-risk but performed unnecessarily in about 20 percent of all cases."
裡面的"performed unnecessarily"指的是"unnecessary removals of the appendix"嗎???

因為我的想法是,
如果要證實這句話"doctors can largely avoid unnecessary removals of the appendix".
除了B的選項,新方法的誤診都是把沒有盲腸炎的病人誤診為有盲腸炎,也就是把沒有盲腸炎的病人割除了盲腸,這個百分之2的"misdiagnoses"就是"unnecessary removals of the appendix".
也必須配合,舊方法的百分之20的"performed unnecessarily"等於"unnecessary removals of the appendix".
這樣才能夠完全的說明"doctors can largely avoid unnecessary removals of the appendix"的這句話.
不知道我的理解正不正確.........
碰到這種繞來繞去的題目.........
唉~~~只能保佑媽祖顯靈,聖母瑪利亞降臨了~~~

[PureRay]

不好意思，我想整理一下自己的思緒，順便看看這樣想有沒有問題

題目要件：

1.減少不該割而割
2.該割的都割了


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

誤診的情況只發生在沒病說成有病，不必要的手術發生率從20%降到2%。同時其他有病的都真的診斷得出來，都割掉了。


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

診斷出來有病的都真的有病，所以診斷有病的都會去割，但是診斷沒病的狀況不明。如果2%的誤診是把有病的診斷成沒病，則會有人該割而未割→無法滿足要件2