87. In tests for pironoma, a serious disease, a false positive result indicates that people have pironoma when, in fact, they do not; a false negative result indicates that people do not have pironoma when, in fact, they do. To detect pironoma most accurately, physicians should use the laboratory test that has the lowest proportion of false positive results.
Which of the following, if true, gives the most support to the recommendation above?
(A) The accepted treatment for pironoma does not have damaging side effects.
(B) The laboratory test that has the lowest proportion of false positive results causes the same minor side effects as do the other laboratory tests used to detect pironoma.
(C) In treating pironoma patients, it is essential to begin treatment as early as possible, since even a week of delay can result in loss of life.
(D) The proportion of inconclusive test results is equal for all laboratory tests used to detect pironoma.
(E) All laboratory tests to detect pironoma have the same proportion of false negative results.
哪位牛人能帮忙分析一下呢？为什么选E
看了楼上给的链接解释如下：
我觉得是这样的：positive即使错了，也只是把没有弄成有；而negative的如果错了的话，就是漏网之鱼，患者有生命危险。
清理上应该倾向于使用positive的测试方法（尽量避免误诊造成的死亡）。但是如果N测试的准确率很高，就可以消除上述的担心。
而 E 所诉，只要用negative的测法，就肯定有误诊。进而支持了使用P测法。
当然隐含的调节是P测法不存在固定错误率的问题，选取其中最优的就是最好的测法。
进一步说明一下， 用negitive的测试结果也能看，只是通过这种结果作判断比较有危险（万一漏看的话，耽误病情阿）。所以支持结论的话，只要所有的negitive测试结果一样的话，就只看positive可以了。
这个题还有一个统计学解法：
[attachimg]65292[/attachimg]
上图H0表示“患病”，H1表示“不患病”
红色区域为 type I error，即 P(reject H0 | H0 true)，即 P( 诊断为不患病 | 患病) = false negative result
蓝色区域为 type II error，即 P(accept H0 | H1 true)，即 P( 诊断为患病 | 不患病) = false positive result
问题转化为：找到一个最精确的诊断方法，即两种错误的概率加起来最小化
思路：如果H0和H1不变，那么一种错误的减小必然使另一种错误变大；现在原文给出了一个方案说最精确的方案是使false positive result最小，即type II error最小，即蓝色区域面积最小，两个参数中只选了控制一个参数，言下之意就是另一个参数恒定；反映在图上就是在红色面积不变的情况下，H1整体往右移
to make it simple:
根据题目，可知：
1. the more accurate test, the less false results
2. false results = positive false + negative false
结论：最少的negative false --> 最少的 false results
可推出：postive false 是一个常量。
这是我的思路
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