Честотите се определят като много чести (≥ 1/ 10), чести (≥ 1/ 100, < 1/ 10), нечести (≥ 1/ 1 000, < 1/ 100), редки (≥ 1/ 10 000, < 1/ 1 000), много редки (< 1/ 10 000), включително изолирани.
The reporting rate is classified as very common (≥ 1/ 10), common (≥ 1/ 100, < 1/ 10), uncommon (≥ 1/ 1,000, < 1/ 100), rare (≥ 1/ 10,000, < 1/ 1,000), very rare (< 1/ 10,000), including isolated.