Explain the difference between relative risk, attributable risk, and population attributable
risk. Provide an example (not from the textbook) of how each type of risk is used in
epidemiology. How would you propose using population attributable risk to advocate for a
health policy or intervention relative to your health interest?

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In epidemiology, the calculation of the level of risk associated with the occurrence of a particular
disease necessitates the comparison of the prevalence of the health condition between the
individuals who experience a risk factor (the exposed) and those who do not (unexposed). More
precisely, the determination of the relative risk involves the calculation of the incidence rates of
the health condition or outcome among the individuals exposed to a factor of interest and the
unexposed (Kirkland, 2019). For instance, epidemiologists use relative risk in the determination
of whether exposure to a specific risk factor such as maternal smoking is associated with an
increase, decrease, or change in the occurrence of the disease or outcome (low birth weight in
newborns) when compared to the unexposed.
Conversely, attributable risk differs from relative risk in that it focuses on the
determination of the extent to which an outcome may be associated with a particular risk factor
within a population (Laake & Benestad, 2015). For instance, in epidemiology, the calculation of
the attributable risk involves the subtraction of the excess vulnerability of the unexposed group
from that of the exposed group. It thus plays an integral role in the provision of estimates related

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to the impact of the poor outcome that could be achieved if the risk factor was reduced or
Similarly, population attributable risk differs from the measures mentioned above in that
it facilitates the determination of the proportion of all cases of an outcome (exposed and
unexposed) in the entire population that could be attributed to the exposure to the risk factors
(Kirkland, 2019). For instance, the calculation of the population attributable risk in epidemiology
involves the evaluation of the excess risk imposed by the exposure to a particular disease or
outcome and the proportion of the entire population under exposure. As such, the use of the
population attributable risk in the advocacy for health policy or intervention relative to a health
interest would occur through the calculation of attributable risks for individual risk factors that
adjust for the influence of other potential risk factors (Laake & Benestad, 2015). This way, the
identification o people at risk for an adverse outcome based on elements such as age groups,
race, behavior, medical conditions, and environmental factors would provide populations for
targeting interventions. It would thus facilitate the development of strategic measures aimed at
mitigating the occurrence or prevalence of such conditions.

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Kirkland, S. A. (2019). Epidemiology: Relative and Attributable Risk.
Laake, P., & Benestad, H. B. (2015). Research in Medical and Biological Sciences: From
Planning and Preparation to Grant Application and Publication. Academic Press.