Много чести (≥1/ 10), чести (≥1/ 100 до < 1/ 10), нечести (≥1/ 1000 до < 1/ 100), редки (≥1/ 10000 до < 1/ 1000), много редки (< 1/ 10000), в това число изолирани случаи.
Frequencies are defined as Very common (≥ 1/ 10) Common (≥ 1/ 100 to < 1/ 10) Uncommon (≥ 1/ 1,000 to < 1/ 100) Rare (≥ 1/ 10,000 to < 1/ 1,000) Very rare (< 1/ 10,000) not known (cannot be estimated from the available data)