How do you interpret the population attributable risk?

Calculating the population attributable risk percent allows you to determine what percent of an outcome could possibly be prevented if a risk factor were to be removed from the population. To calculate the attributable risk, one simply subtracts the risk for the non-exposed group from the risk for the exposed group.

What is the population attributable fraction PAF?

The population Attributable Fraction (PAF) is the proportion of cases for an outcome that can be attributed to a certain risk factor among the entire population (3). Therefore, it would be possible to estimate PAF using epidemiological data on the prevalence of exposure and the relative risk of disease.

How do you read etiological fractions?

Etiologic fraction = [ a / ( a + b ) − c / ( c + d ) ] 1 − [ c / ( c + d ) ] (population attributable risk). The relative risk used by epidemiologists for prospective studies differs slightly from the odds ratio used in case–control studies and is defined as a/(ac)/b(bd).

How do you calculate attributable fractions in epidemiology?

Attributable Proportion Among the Exposed It is calculated by taking the risk difference, dividing it by the incidence in the exposed group, and then multiplying it by 100 to convert it into a percentage.

What is the fraction of the population?

Definition: The population attributable fraction is the proportional reduction in population disease or mortality would occur if exposure to a risk factor were reduced to an alternative ideal exposure scenario.

What is the difference between attributable risk and attributable fraction?

Attributable Risk(AR) (sometimes called Attributable Proportion or Attributable Fraction) is a measure of the prevalence of a condition or disease. Given a group of people exposed to a risk, it’s the fraction who develop a disease or condition.

Why population attributable fractions can sum to more than one?

PAFs can sum to more than 1 because some individuals with more than one risk factor can have disease prevented in more than one way, and the prevented cases of these individuals could be counted more than once.

What is a fraction of the population?

How do you find fractions in statistics?

The sampling fraction is the proportion of a population to be included in a sample . The sampling fraction is equal to the sample size divided by the population size, n/N.

How does the attributable proportion among the exposed relate to the attributable proportion in the total population?

Attributable proportion It further assumes that if the risk of disease in the exposed group is higher than the risk in the unexposed group, the difference can be attributed to the exposure. Thus, the attributable proportion is the amount of disease in the exposed group attributable to the exposure.

What is the name of the Population Attributable fraction?

PAR is the difference in the rate or risk of disease for the population compared to the unexposed. 1 2 4 there is great vagueness in the use of terminology. Other common names used are ‘population attributable risk percent’, ‘excess fraction’, ‘etiological fraction’ and ‘attributable fraction’.

When was Population Attributable fraction ( PAF ) first used?

The development of the original population attributable fraction (PAF) dates back to 19531 and it has been widely used, misused and miscalled since then. We discuss two main issues here: use of appropriate terminology and calculations of the PAF, and of the potential impact fraction (PIF).

How to calculate the population attributable risk percent?

Calculating the population attributable risk percent allows you to determine what percent of an outcome could possibly be prevented if a risk factor were to be removed from the population. To calculate the attributable risk, one simply subtracts the risk for the non-exposed group from the risk for the exposed group.

What is the attributable fraction for the exposed group?

However, not all of these diseased cases can be attributed to the exposure.We know from our previous calculation of the attributable fraction in the exposed group that the attributable fraction for the exposed group was 0.8, or 80%.