More on Risk: Estimating the Potential for Prevention

Vocabulary flashcards covering the concepts, formulas, and clinical applications of attributable risk and population attributable risk for estimating prevention potential.

Attributable risk

The amount or proportion of disease incidence (or disease risk) that can be attributed to a specific exposure, indicating how much disease could be prevented if exposure were eliminated.

Prerequisite for estimating attributable risk

A condition requiring reasonable certainty that the association between the risk factor and the disease is causal before calculating attributable risk.

Attributable risk for the exposed group (Absolute)

The incidence of disease among exposed individuals that is directly attributable to the exposure, calculated as: $(\text{Incidence in exposed group}) - (\text{Incidence in unexposed group})$.

Background risk

The baseline or residual risk of disease in a population that is not due to the exposure of interest, represented by the disease incidence in the unexposed group.

Attributable risk proportion for the exposed group

The proportion of disease incidence among exposed individuals that is directly due to the exposure, calculated as: $\frac{(\text{Incidence in exposed group}) - (\text{Incidence in unexposed group})}{\text{Incidence in exposed group}}$.

Total incidence components in the exposed group

The overall disease incidence in the exposed cohort, which equals the sum of the background incidence (incidence not due to the exposure) and the incidence attributable to the exposure.

Population attributable risk (PAR)

The disease incidence in a total population (including both exposed and unexposed individuals) that can be attributed to a specific exposure, calculated as: $(\text{Incidence in total population}) - (\text{Incidence in unexposed group})$.

Population attributable risk proportion (%PAR)

The fraction of disease incidence in the total population attributable to a specific exposure, calculated as: $\frac{(\text{Incidence in total population}) - (\text{Incidence in unexposed group})}{\text{Incidence in total population}}$.

Leading global risk factor cluster for mortality (2010)

Dietary risk factors and physical inactivity, which accounted for $30.6\%$ of attributable deaths ($12,503,370$ deaths) worldwide in 2010.

Relative risk and Odds ratio

Epidemiologic measures that quantify the strength of an association, serve as crucial considerations for causal inference, and are primarily valuable in etiologic studies of disease.

Relative risk versus Attributable risk

Relative risk measures the strength of association to infer causality in etiologic studies, whereas attributable risk measures the potential impact of removing an exposure on disease occurrence for clinical and public health prevention.

Attributable risk calculation (Smoking and CHD study)

Using the 10-year study cohort, the incidence of CHD in smokers attributable to smoking is $27.5$ per $1,000$ ($0.0325 - 0.0050$), and the attributable proportion among smokers is $84.6\%$ ($\frac{0.0275}{0.0325} \times 100\%$).