Post by Admin on Feb 15, 2016 1:02:48 GMT
A research group calculates the risk of developing lung cancer in nonsmokers as 1%, and the risk of developing lung cancer in smokers as 49%.
What is the attributable risk of smoking in the development of lung cancer?
A.
0.048
B.
0.22
C.
0.48
D.
0.49
E.
0.50
Attributable risk, also known as the risk difference, can be explained as the excess risk that is associated with a certain exposure. It is a measure of absolute risk. Attributable risk takes into account the background rate of the disease. It is calculated by subtracting the incidence of the disease in nonexposed persons (nonsmokers, in this case 1%) from the incidence of disease in those exposed (smokers, in this case 49%). Thus 0.49 – 0.01 = 0.48, or 48%.
A is not correct. 3% chose this.
This answer is off by a factor of 10.
B is not correct. 4% chose this.
This answer subtracts the percentage of participants incidentally exposed to secondhand smoke from the incidence of lung cancer in smokers and is therefore not a valid number. The attributable risk of smoking is not affected by the occasional exposure to secondhand smoke, as both groups were exposed equally to this factor.
D is not correct. 14% chose this.
The attributable risk is not just the incidence of disease in those exposed (smokers), it also must take into account the risk of disease in the unexposed.
E is not correct. 5% chose this.
The attributable risk is calculated by subtracting, not adding, the incidence of the disease in nonexposed persons (nonsmokers) from the incidence of disease in those exposed (smokers).
Bottom Line:
C. Attributable risk, or risk difference, is calculated by subtracting the incidence of disease in nonexposed persons from the incidence of disease in exposed persons.
for year: 2015
What is the attributable risk of smoking in the development of lung cancer?
A.
0.048
B.
0.22
C.
0.48
D.
0.49
E.
0.50
Attributable risk, also known as the risk difference, can be explained as the excess risk that is associated with a certain exposure. It is a measure of absolute risk. Attributable risk takes into account the background rate of the disease. It is calculated by subtracting the incidence of the disease in nonexposed persons (nonsmokers, in this case 1%) from the incidence of disease in those exposed (smokers, in this case 49%). Thus 0.49 – 0.01 = 0.48, or 48%.
A is not correct. 3% chose this.
This answer is off by a factor of 10.
B is not correct. 4% chose this.
This answer subtracts the percentage of participants incidentally exposed to secondhand smoke from the incidence of lung cancer in smokers and is therefore not a valid number. The attributable risk of smoking is not affected by the occasional exposure to secondhand smoke, as both groups were exposed equally to this factor.
D is not correct. 14% chose this.
The attributable risk is not just the incidence of disease in those exposed (smokers), it also must take into account the risk of disease in the unexposed.
E is not correct. 5% chose this.
The attributable risk is calculated by subtracting, not adding, the incidence of the disease in nonexposed persons (nonsmokers) from the incidence of disease in those exposed (smokers).
Bottom Line:
C. Attributable risk, or risk difference, is calculated by subtracting the incidence of disease in nonexposed persons from the incidence of disease in exposed persons.
for year: 2015