Incidence and prevalence are formally defined on slide 7. Birth and death rates are also estimates of absolute risk.

Risk factors are identified by determining whether they significantly increase or decrease the risk of developing a disease. The magnitude of increased/decreased risk is expressed as a relative risk or odds ratio, which are defined in slide 8.

Attributable risk/fraction is defined on slide 9, and represents the incidence/proportion of disease risk that is attributable to the risk factor. It represents the amount that could be prevented if the risk factor was eliminated.