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The incidence of carcinoma cervix in women with multiple sexual partners is 5 times the incidence seen in those with a single partner. Based on this, what is the attributable risk?
The incidence of carcinoma cervix in women with multiple sexual partners is 5 times the incidence seen in those with a single partner. Based on this, what is the attributable risk?
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Attributable risk percent equals (RR minus 1) divided by RR, then multiplied by 100.
Updated On: Jul 8, 2026
- 20%
- 40%
- 50%
- 80%
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The Correct Option is D
Solution and Explanation
Step 1: Name what is given.
Women with many partners get carcinoma cervix $5$ times as often as women with one partner. This ratio of incidences is the relative risk, so $RR=5$.
Step 2: Understand what attributable risk means.
Out of all the disease seen in the exposed group, some part would have happened anyway due to other causes, and some part is truly caused by the exposure. Attributable risk percent picks out that second part, as a percentage of the total risk in the exposed group.
Step 3: Use the shortcut formula built from RR.
\[ AR\% = \frac{RR-1}{RR}\times100 \]
This works because if incidence in the unexposed is $I_0$, incidence in the exposed is $RR \times I_0$, and the extra risk due to exposure is $(RR-1)I_0$. Dividing this extra part by the total exposed incidence $RR \times I_0$ gives the same formula.
Step 4: Plug in $RR=5$.
\[ AR\% = \frac{5-1}{5}\times100 = \frac{4}{5}\times100 \]
Step 5: Finish the arithmetic.
\[ AR\% = 80\% \]
\[ \boxed{80\%} \]
Women with many partners get carcinoma cervix $5$ times as often as women with one partner. This ratio of incidences is the relative risk, so $RR=5$.
Step 2: Understand what attributable risk means.
Out of all the disease seen in the exposed group, some part would have happened anyway due to other causes, and some part is truly caused by the exposure. Attributable risk percent picks out that second part, as a percentage of the total risk in the exposed group.
Step 3: Use the shortcut formula built from RR.
\[ AR\% = \frac{RR-1}{RR}\times100 \]
This works because if incidence in the unexposed is $I_0$, incidence in the exposed is $RR \times I_0$, and the extra risk due to exposure is $(RR-1)I_0$. Dividing this extra part by the total exposed incidence $RR \times I_0$ gives the same formula.
Step 4: Plug in $RR=5$.
\[ AR\% = \frac{5-1}{5}\times100 = \frac{4}{5}\times100 \]
Step 5: Finish the arithmetic.
\[ AR\% = 80\% \]
\[ \boxed{80\%} \]
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