Table 1.

Formula for calculating Number of Events Prevented in your Population (NEPP)

NEPP = n * Pd * Pe * ru * RRR where
n = population size
Pd = the prevalence of the disease in the population
Pe = the proportion eligible for treatment
ru = the risk of the event of interest in the untreated group or baseline risk
RRR = the relative risk reduction associated with the treatment

In order to reflect the incremental effect of changing from current to 'best' practice and to adjust for levels of compliance the proportion eligible for treatment P_e is ((P_b - P_t) * P_c where P_t is the proportion currently treated, P_b is the proportion that would be treated if best practice was adopted and P_c is the proportion of the population who are compliant with (adherent to) their medication.