scientists

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scientists

by gmatmachoman » Sun Jan 31, 2010 4:23 am
Reporter: A team of scientists has recently devised a new test that for the first time accurately diagnoses autism in children as young as 18 months old. When used to evaluate 16,000 children at their 18-month checkup, the test correctly diagnosed all 10 children later confirmed to be autistic, though it also wrongly identified 2 children as autistic. Autistic children can therefore now benefit much earlier in life than before from the treatments already available.

Which one of the following is an assumption on which the reporter's argument depends?

A) No test intended for diagnosing autism at such an early age existed before the new test was devised.

B) A diagnostic test that sometimes falsely gives a positive diagnosis can still provide a reasonable basis for treatment decisions.

C) The new test can be used to evaluate all children. regardless of the level of development of their verbal skills.

D) Those children incorrectly identified as autistic will not be adversely affected by treatments aimed at helping autistic children.

E) There was no reliable evidence that autism could affect children so young until the advent of the new test.
Source: — Critical Reasoning |

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by fibbonnaci » Sun Jan 31, 2010 7:03 am
A) No test intended for diagnosing autism at such an early age existed before the new test was devised. [ this is a fact stated in the stimulus and not an assumption.]

B) A diagnostic test that sometimes falsely gives a positive diagnosis can still provide a reasonable basis for treatment decisions. [ Correct! you can prove this by negating the option. the conclusion falls apart in that case]

C) The new test can be used to evaluate all children. regardless of the level of development of their verbal skills. [ clearly out of scope. assumption does not involve verbal skills anyway!]

D) Those children incorrectly identified as autistic will not be adversely affected by treatments aimed at helping autistic children. [ nice catch. though this might look like a defender assumption but it is not. the conclusion deals with only autistic children getting benefited with the treatments. non autistic children is out of scope]

E) There was no reliable evidence that autism could affect children so young until the advent of the new test. [ again a restatement of A. eliminated!]

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by komal » Sun Jan 31, 2010 7:05 am
gmatmachoman wrote:Reporter: A team of scientists has recently devised a new test that for the first time accurately diagnoses autism in children as young as 18 months old. When used to evaluate 16,000 children at their 18-month checkup, the test correctly diagnosed all 10 children later confirmed to be autistic, though it also wrongly identified 2 children as autistic. Autistic children can therefore now benefit much earlier in life than before from the treatments already available.

Which one of the following is an assumption on which the reporter's argument depends?

A) No test intended for diagnosing autism at such an early age existed before the new test was devised.
Incorrect : Just because the stimulus says that a new test ACCURATELY diagnoses autism does not mean that there was NO TEST existed. It is possible that there existed a test but which DID NOT ACCURATELY diagnosed autism.

B) A diagnostic test that sometimes falsely gives a positive diagnosis can still provide a reasonable basis for treatment decisions.
Correct : This is the most appropriate assumption because it follows the premise that states 2 children were wrongly identified as autistic out of 10.

C) The new test can be used to evaluate all children. regardless of the level of development of their verbal skills.
Incorrect : Clearly out of scope.

D) Those children incorrectly identified as autistic will not be adversely affected by treatments aimed at helping autistic children.
Incorrect : Irrelevant. Issue is not about effects of treatments aimed at helping autistic children.

E) There was no reliable evidence that autism could affect children so young until the advent of the new test.
Incorrect : Irrelevant