Table 1 Values and interpretation of the Spatial Incidence Ratio

SIR(a_i) = 0

When the geo-object under study has no epidemiological incidence

0 < SIR(a_i) < 0.5

The SIR is less than half of the total incidence of the geographical region

0.5 ≤ SIR(a_i) < 1.0

SIR is more than half of the total incidence, but is less than the epidemiological incidence of the geographical region

1.0 ≤ SIR(a_i) < 1.5

Then SIR is higher than the total incidence of the geographical region by less than 50%

1.5 ≤ SIR(a_i) < 2.0

The SIR exceeds the global incidence of the geographical region by more than 50%

SIR(a_i) ≥ 2.0

Then SIR is two or more times higher than the total incidence of the geographical region