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* biostat q...answer needed fast!!
 #846223  
  drangel2014 - 12/10/17 20:07
 
  in a small observational study, 100 industrial workers are followed for one year to assess for the development of respiratory symptoms. 30 out of 60 smokers experience respiratory symptoms vs 10 out of 40 non-smokers. what percentage of respiratory disease experienced by all study subjects is attributed to smoking?

a) 75%
b) 50%
c) 25%
d) 20%
e) 10%

plz also share how you got the answer. thx.
 
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* Re:biostat q...answer needed fast!!
#3354813
  drpaulpogba - 12/10/17 21:52
 
  Question asks for AR.....ie Incidence in exposed- incidence in unexposed

30/60 - 10/40

Thus C ie 25%
 
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* Re:biostat q...answer needed fast!!
#3354821
  mona91 - 12/11/17 00:39
 
  it is A 75%  
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* Re:biostat q...answer needed fast!!
#3354893
  cardio69 - 12/11/17 20:49
 
  Question ask "what % of respiratory disease experienced by 'ALL' study subjects is attributed to SMOKING?"


To determine population attributable risk percent/PAR%
= Risk (total) – Risk (unexposed) /Risk (total) X 100
30 smoker and 10 unexposed/non who dev disease out of 100. 30 +10 = 40/100 overall incidence disease
Different in risk of dev disease btw smokers & study population “AS A WHOLE” as q asking
(30/60 minus 40/100 -> 0.5 – 0.4 = 0.1) divided by incidence of disease in SMOKERS which is 0.5 = 0.2 X100 or 20% of yearly disease in study case population is attributable to SMOKING

Ans should be D :)
 
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* Re:biostat q...answer needed fast!!
#3355005
  drangel2014 - 12/12/17 23:19
 
  thank you cardio :)  
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* Re:biostat q...answer needed fast!!
#3355201
  rulad89 - 12/14/17 23:11
 
  thank you  
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* Re:biostat q...answer needed fast!!
#3355208
  cardio69 - 12/14/17 23:21
 
  Glad I could help:)  
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* Re:biostat q...answer needed fast!!
#3355223
  willywhy89 - 12/15/17 07:43
 
  nice puzzle :)  
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* Re:biostat q...answer needed fast!!
#3356094
  lamonti - 12/26/17 08:29
 
  Cardio69,

Your equation is like IE - IP / IE

While PAR% equation is IP - INE / IP, this equation doesn't give 20% as an answer

IE: incidence in exposed
INE: incidence in non-exposed
IP: incidence in population

Can you use this equation for PAR%: P(RR-1)/P(RR-1)+1, will you get 20%?

Thanks!
 
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* Re:biostat q...answer needed fast!!
#3356156
  cardio69 - 12/27/17 16:47
 
  @lamonti U mixing it up
Put this Q into the equation for me:
Q) Among the general population what % of the TOTAL risk for the disease is due to the risk factor?
 
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* Re:biostat q...answer needed fast!!
#3356187
  lamonti - 12/28/17 12:57
 
  That's what is I am saying. Population attributable risk percent [PAR%]

You didn't use the formal equations for PAR%
 
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