While proponents argue about the benefits of vaccination for children

Question

While proponents argue about the benefits of vaccination for children, there is hardly any concrete data to back up their claims. Not only is the efficacy of the vaccines questionable but there are also possible chances that vaccines cause various illnesses such as autism. Children who have been vaccinated have a probability of 0.8% of getting the diseases that they have been vaccinated against while the national average of all the children who get the disease, including the children who have not been vaccinated, is 0.85%. So, there is hardly any improvement in the prevention rate because of vaccination.

Which of the following options would help the most to evaluate the given argument?

A. What is the ratio of the number of children who are not vaccinated to the number of children who are vaccinated in the country?

B. What number of children are vaccinated in the country?

C. What percentage of children have access to vaccination and healthcare?

D. What is the national average of children with autism ?

E. What is the method used to measure the efficacy of vaccines?

I have tweaked the options to make a subtle point.

Enjoy solving!!

balaji4799 · Answer

Assume there are 100 children in the village. 
1) if all 100 are vaccinated, the probability of catching disease is 80/100 = 0.8%
2) Now if <100 are vaccinated, the probability of catching disease is 85/(100) = 0.85%. Now the denominator includes both (Vaccinated + Non vaccinated children). Now to evaluate if the vaccinations are effective, it is important to know how much proportion of the denominator are vaccinated or non vaccinated. Suppose if 10 vaccinated & 90 non vaccinated then we could think that vaccines are effective. Suppose if 90 are vaccinated and 10 are non vaccinated then the vaccines are ineffective because, vaccinated people got the disease. 
Hence, in my opinion (IMO) option A is needed to evaluate this argument.

Please advise if I am inaccurate and misleading. I am happy to learn.

Abhishek009 · Answer

This is a very good question in my opinion..

The highlighted parts in the stimulus are the key points for this question...

Let there be 10000 children
Say 1000 children are vaccinated...

So, out of 1000 children 8 children will have the probability of getting diseases

So, out of 10000 children 85 children will have the probability of getting diseases

Now the author claims -
 Though we have taken example of 10000 children among which 1000 children have been vaccinated , the number of children vaccinated may be higher ...

Let there be 10000 children
Say 9000 children are vaccinated...

So, out of 9000 children 72 children will have the probability of getting diseases
And out of 10000 children 85 children will have the probability of getting diseases
  
Thus in this case there is a negligible difference between vaccination and non vaccination  
  
Thus based on this observation option (A) is absolutely correct...

balaji4799    your approach seems correct , no issues ...

jaisonsunny77 · Answer

Conclusion: there is hardly any improvement in the prevention rate because of vaccination.

A. What is the ratio of the number of children who are not vaccinated to the number of children who are vaccinated in the country? - (A) would give us a solid understanding over the difference in number between those who have been vaccinated and those who have not been vaccinated. Knowing this difference will help us evaluate the conclusion. Hence,    (A) is the right answer choice.  
   
B. What number of children are vaccinated in the country?  -  this does not expose the ''number'' of children who are 'not' vaccinated. Without knowing this number, we cannot evaluate the conclusion. 
 
C. What percentage of children have access to vaccination and healthcare?  -  has no bearing on the conclusion. 
  
D. What is the national average of children with autism ?  -  irrelevant. 
  
E. What is the method used to measure the efficacy of vaccines?  -  irrelevant.

VerbalBot · Answer

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While proponents argue about the benefits of vaccination for children

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While proponents argue about the benefits of vaccination for children

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