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How can I convert relative risk into absolute risk?

How can I estimate absolute risk for an individual from the available sources of RR and OR?

Silverfish
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user43446
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    This is clearly a home-work. Read the home-work posting guidelines – Aksakal Jun 01 '15 at 15:04
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    Agree with Aksakal but it is still a very important question in my opinion. However, the user could specify which relative risk he means, as there are several types of relativity; odds ratios, pure relative risks, hazard ratios, and the conversion to absolute risk differs between these. This could be helpful: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1117211/ – Adam Robinsson Jul 02 '15 at 08:21

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Absolute risk is the risk (or prevalence within the group) that a group has X. For example, if 10% of men have cancer, the absolute risk of cancer in men is 10%.

Relative risk is the ratio of this risk between two groups (e.g., 2 to 1). So if men are twice as likely to have cancer compared to women, the relative risk is 2 to 1.

To calculate absolute risk from relative risk, you need to know the absolute risk for at least one of the groups. So if the relative risk for men of having X compared to women having X is 3, and you know the absolute risk of X in women is 1/100, then you know the absolute risk of having X in men is 3/100. If you do not know the absolute risk in either group you cannot calculate absolute risk.

Behacad
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