There
is a great deal of geographical variation in the frequency of many
surgical procedures-up to tenfold variation per hundred thousand people
among different areas in the numbers of hysterectomies,
prostatectomies, and tonsillectomies.
To support a conclusion
that much of the variation is due to unnecessry surgical procedures, it
would be most important to establish which of the following?
A. A
local board of review at each hospital examines the records of every
operation to determine whether the surgical procesure was necessary.
B.
The variation is unrelated to factors (other than the surgical
procedures themselves) that influence the incidence of diseases for
which surgery might be considnered.
C. There are several categoreis
of surgical procedures(other than hysterctomies, prostatectomies, and
tonsillectomies)that are often performed unnecessarily.
D. For
certain surgical procedures, it is difficult to determine after the
operation whether the procedures were necessary or whether alternativev
treatment would have succeeded.
E. With respect to how often they
are performed unnecessarily, hysterectomies, prostatectomies, and
tonsillectomies are representative of surgical procedures in general.
Answer B
这道题目我一头雾水，请高人帮我分析一下。作者: tracy214wxy 时间: 2011-10-4 21:13
典型的排除他因。。。解释如下。
Conclusion: much of the variation is due to unnecessry surgical procedures => (not something else)
Premises: 1) great deal of geographical variation in the frequency of many surgical procedures
Support??
you want to find another piece of information that support that it is unnecessry surgical procedures that lead to big variation.
B) get rid of the possible other factors that might lead to the same outcome. no other factors are considered.
A) irrelevant. it does nothing to support the conclusion. it merely tells you a fact maybe.
C) irrelevant. we dont care about others.
D) irrelevant
E) again, irrelevant.作者: YEWCHOW 时间: 2011-10-6 21:31
